style(clang-format): add Clang-Format configuration

Add a configuration for the Clang-Format C and C++ code style formatter.
This is based on the Clang-Format used by the Linux kernel with some
minor modifications:

- the for-each macros reflect what we have available in TF-A
- sorting of include files roughly follows our existing strategy

Change-Id: I8366c935a146175c14249e084a8328bbba05c7c8
Signed-off-by: Chris Kay <chris.kay@arm.com>
diff --git a/.clang-format b/.clang-format
new file mode 100644
index 0000000..6a89eeb
--- /dev/null
+++ b/.clang-format
@@ -0,0 +1,199 @@
+---
+AccessModifierOffset: -4
+AlignAfterOpenBracket: Align
+AlignArrayOfStructures: None
+AlignConsecutiveMacros: None
+AlignConsecutiveAssignments: None
+AlignConsecutiveBitFields: None
+AlignConsecutiveDeclarations: None
+AlignEscapedNewlines: Left
+AlignOperands:   Align
+AlignTrailingComments: false
+AllowAllArgumentsOnNextLine: true
+AllowAllParametersOfDeclarationOnNextLine: false
+AllowShortEnumsOnASingleLine: true
+AllowShortBlocksOnASingleLine: Never
+AllowShortCaseLabelsOnASingleLine: false
+AllowShortFunctionsOnASingleLine: None
+AllowShortLambdasOnASingleLine: All
+AllowShortIfStatementsOnASingleLine: Never
+AllowShortLoopsOnASingleLine: false
+AlwaysBreakAfterDefinitionReturnType: None
+AlwaysBreakAfterReturnType: None
+AlwaysBreakBeforeMultilineStrings: false
+AlwaysBreakTemplateDeclarations: MultiLine
+AttributeMacros:
+  - __capability
+BinPackArguments: true
+BinPackParameters: true
+BraceWrapping:
+  AfterCaseLabel:  false
+  AfterClass:      false
+  AfterControlStatement: Never
+  AfterEnum:       false
+  AfterFunction:   true
+  AfterNamespace:  true
+  AfterObjCDeclaration: false
+  AfterStruct:     false
+  AfterUnion:      false
+  AfterExternBlock: false
+  BeforeCatch:     false
+  BeforeElse:      false
+  BeforeLambdaBody: false
+  BeforeWhile:     false
+  IndentBraces:    false
+  SplitEmptyFunction: true
+  SplitEmptyRecord: true
+  SplitEmptyNamespace: true
+BreakBeforeBinaryOperators: None
+BreakBeforeConceptDeclarations: true
+BreakBeforeBraces: Custom
+BreakBeforeInheritanceComma: false
+BreakInheritanceList: BeforeColon
+BreakBeforeTernaryOperators: false
+BreakConstructorInitializersBeforeComma: false
+BreakConstructorInitializers: BeforeComma
+BreakAfterJavaFieldAnnotations: false
+BreakStringLiterals: false
+ColumnLimit:     80
+CommentPragmas:  '^ IWYU pragma:'
+QualifierAlignment: Leave
+CompactNamespaces: false
+ConstructorInitializerIndentWidth: 8
+ContinuationIndentWidth: 8
+Cpp11BracedListStyle: false
+DeriveLineEnding: true
+DerivePointerAlignment: false
+DisableFormat:   false
+EmptyLineAfterAccessModifier: Never
+EmptyLineBeforeAccessModifier: LogicalBlock
+ExperimentalAutoDetectBinPacking: false
+PackConstructorInitializers: BinPack
+BasedOnStyle:    ''
+ConstructorInitializerAllOnOneLineOrOnePerLine: false
+AllowAllConstructorInitializersOnNextLine: true
+FixNamespaceComments: false
+ForEachMacros:
+  - fdt_for_each_compatible_node
+  - fdt_for_each_property_offset
+  - fdt_for_each_subnode
+  - for_each_err_record_info
+  - for_each_subscriber
+IfMacros:
+  - KJ_IF_MAYBE
+IncludeBlocks:   Regroup
+IncludeCategories:
+  - Regex:           '^<(assert|complex|ctype|errno|fenv|float|inttypes|iso646|limits|locale|math|setjmp|signal|stdalign|stdarg|stdatomic|stdbool|stdckdint|stddef|stdint|stdio|stdlib|stdnoreturn|string|tgmath|threads|time|uchar|wchar|wctype)\.h>$'
+    Priority:        0
+    SortPriority:    0
+    CaseSensitive:   false
+  - Regex:           '^<lib/(compiler-rt|libfdt|mbedtls|zlib)/.+>$'
+    Priority:        1
+    SortPriority:    0
+    CaseSensitive:   false
+  - Regex:           '^<(platform(_def)?\.h)|(plat[_/].+)>$'
+    Priority:        2
+    SortPriority:    0
+    CaseSensitive:   false
+  - Regex:           '^<.+>$'
+    Priority:        3
+    SortPriority:    0
+    CaseSensitive:   false
+  - Regex:           '^".+"$'
+    Priority:        4
+    SortPriority:    0
+    CaseSensitive:   false
+IncludeIsMainRegex: '(Test)?$'
+IncludeIsMainSourceRegex: ''
+IndentAccessModifiers: false
+IndentCaseLabels: false
+IndentCaseBlocks: false
+IndentGotoLabels: false
+IndentPPDirectives: None
+IndentExternBlock: AfterExternBlock
+IndentRequires:  false
+IndentWidth:     8
+IndentWrappedFunctionNames: false
+InsertTrailingCommas: None
+JavaScriptQuotes: Leave
+JavaScriptWrapImports: true
+KeepEmptyLinesAtTheStartOfBlocks: false
+LambdaBodyIndentation: Signature
+MacroBlockBegin: ''
+MacroBlockEnd:   ''
+MaxEmptyLinesToKeep: 1
+NamespaceIndentation: None
+ObjCBinPackProtocolList: Auto
+ObjCBlockIndentWidth: 8
+ObjCBreakBeforeNestedBlockParam: true
+ObjCSpaceAfterProperty: true
+ObjCSpaceBeforeProtocolList: true
+PenaltyBreakAssignment: 10
+PenaltyBreakBeforeFirstCallParameter: 30
+PenaltyBreakComment: 10
+PenaltyBreakFirstLessLess: 0
+PenaltyBreakOpenParenthesis: 0
+PenaltyBreakString: 10
+PenaltyBreakTemplateDeclaration: 10
+PenaltyExcessCharacter: 100
+PenaltyReturnTypeOnItsOwnLine: 60
+PenaltyIndentedWhitespace: 0
+PointerAlignment: Right
+PPIndentWidth:   -1
+ReferenceAlignment: Pointer
+ReflowComments:  false
+RemoveBracesLLVM: false
+SeparateDefinitionBlocks: Leave
+ShortNamespaceLines: 1
+SortIncludes:    CaseInsensitive
+SortJavaStaticImport: Before
+SortUsingDeclarations: false
+SpaceAfterCStyleCast: false
+SpaceAfterLogicalNot: false
+SpaceAfterTemplateKeyword: true
+SpaceBeforeAssignmentOperators: true
+SpaceBeforeCaseColon: false
+SpaceBeforeCpp11BracedList: false
+SpaceBeforeCtorInitializerColon: true
+SpaceBeforeInheritanceColon: true
+SpaceBeforeParens: ControlStatementsExceptControlMacros
+SpaceBeforeParensOptions:
+  AfterControlStatements: true
+  AfterForeachMacros: false
+  AfterFunctionDefinitionName: false
+  AfterFunctionDeclarationName: false
+  AfterIfMacros:   false
+  AfterOverloadedOperator: false
+  BeforeNonEmptyParentheses: false
+SpaceAroundPointerQualifiers: Default
+SpaceBeforeRangeBasedForLoopColon: true
+SpaceInEmptyBlock: false
+SpaceInEmptyParentheses: false
+SpacesBeforeTrailingComments: 1
+SpacesInAngles:  Never
+SpacesInConditionalStatement: false
+SpacesInContainerLiterals: false
+SpacesInCStyleCastParentheses: false
+SpacesInLineCommentPrefix:
+  Minimum:         1
+  Maximum:         -1
+SpacesInParentheses: false
+SpacesInSquareBrackets: false
+SpaceBeforeSquareBrackets: false
+BitFieldColonSpacing: Both
+Standard:        c++03
+StatementAttributeLikeMacros:
+  - Q_EMIT
+StatementMacros:
+  - Q_UNUSED
+  - QT_REQUIRE_VERSION
+TabWidth:        8
+UseCRLF:         false
+UseTab:          Always
+WhitespaceSensitiveMacros:
+  - STRINGIZE
+  - PP_STRINGIZE
+  - BOOST_PP_STRINGIZE
+  - NS_SWIFT_NAME
+  - CF_SWIFT_NAME
+...