refactor(lib): define GRANULE_SHIFT as parameter

GRANULE_SHIFT is defined as build time parameter instead of
GRANULE_SIZE. This makes it possible to derive GRANULE_SIZE and
GRANULE_MASK from a single value.

Change-Id: I8e6a7aa148aade9921b062702b24111d96107dbf
Signed-off-by: Mate Toth-Pal <mate.toth-pal@arm.com>
diff --git a/docs/getting_started/build-options.rst b/docs/getting_started/build-options.rst
index b863cd5..d4fe338 100644
--- a/docs/getting_started/build-options.rst
+++ b/docs/getting_started/build-options.rst
@@ -229,7 +229,7 @@
    RMM_ARCH			,aarch64 | fake_host	,aarch64		,"Target Architecture for RMM build"
    RMM_MAX_SIZE			,			,0x0			,"Maximum size for RMM image"
    MAX_CPUS			,			,16			,"Maximum number of CPUs supported by RMM"
-   GRANULE_SIZE			,			,4096			,"Granule Size used by RMM"
+   GRANULE_SHIFT		,			,12			,"Granule Shift used by RMM"
    RMM_DOCS			,ON | OFF		,OFF			,"RMM Documentation build"
    CMAKE_BUILD_TYPE		,Debug | Release	,Release		,"CMake Build type"
    CMAKE_CONFIGURATION_TYPES	,Debug & Release	,Debug & Release	,"Multi-generator configuration types"