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/el3_runtime/cpu_data.h b/include/lib/el3_runtime/cpu_data.h
index 9e1d7f1..66c47ab 100644
--- a/include/lib/el3_runtime/cpu_data.h
+++ b/include/lib/el3_runtime/cpu_data.h
@@ -49,7 +49,7 @@
 #define CPU_DATA_PMF_TS0_IDX		0
 #endif
 
-#ifndef __ASSEMBLY__
+#ifndef __ASSEMBLER__
 
 #include <arch_helpers.h>
 #include <lib/cassert.h>
@@ -161,5 +161,5 @@
 						sizeof(((cpu_data_t *)0)->_m))
 
 
-#endif /* __ASSEMBLY__ */
+#endif /* __ASSEMBLER__ */
 #endif /* CPU_DATA_H */