Replace __ASSEMBLY__ with compiler-builtin __ASSEMBLER__

NOTE: __ASSEMBLY__ macro is now deprecated in favor of __ASSEMBLER__.

All common C compilers predefine a macro called __ASSEMBLER__ when
preprocessing a .S file. There is no reason for TF-A to define it's own
__ASSEMBLY__ macro for this purpose instead. To unify code with the
export headers (which use __ASSEMBLER__ to avoid one extra dependency),
let's deprecate __ASSEMBLY__ and switch the code base over to the
predefined standard.

Change-Id: Id7d0ec8cf330195da80499c68562b65cb5ab7417
Signed-off-by: Julius Werner <jwerner@chromium.org>
diff --git a/include/lib/psci/psci.h b/include/lib/psci/psci.h
index fe279d4..04e5e3d 100644
--- a/include/lib/psci/psci.h
+++ b/include/lib/psci/psci.h
@@ -166,7 +166,7 @@
 #define PSCI_RESET2_TYPE_ARCH		(U(0) << PSCI_RESET2_TYPE_VENDOR_SHIFT)
 #define PSCI_RESET2_SYSTEM_WARM_RESET	(PSCI_RESET2_TYPE_ARCH | U(0))
 
-#ifndef __ASSEMBLY__
+#ifndef __ASSEMBLER__
 
 #include <stdint.h>
 
@@ -348,6 +348,6 @@
 void __dead2 psci_power_down_wfi(void);
 void psci_arch_setup(void);
 
-#endif /*__ASSEMBLY__*/
+#endif /*__ASSEMBLER__*/
 
 #endif /* PSCI_H */