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/cpus/aarch64/cortex_a75.h b/include/lib/cpus/aarch64/cortex_a75.h
index 204bfdd..e5ca1ba 100644
--- a/include/lib/cpus/aarch64/cortex_a75.h
+++ b/include/lib/cpus/aarch64/cortex_a75.h
@@ -41,7 +41,7 @@
 #define CORTEX_A75_AMU_GROUP0_MASK	U(0x7)
 #define CORTEX_A75_AMU_GROUP1_MASK	(U(0) << 3)
 
-#ifndef __ASSEMBLY__
+#ifndef __ASSEMBLER__
 #include <stdint.h>
 
 uint64_t cortex_a75_amu_cnt_read(int idx);
@@ -50,6 +50,6 @@
 unsigned int cortex_a75_amu_read_cpuamcntenclr_el0(void);
 void cortex_a75_amu_write_cpuamcntenset_el0(unsigned int mask);
 void cortex_a75_amu_write_cpuamcntenclr_el0(unsigned int mask);
-#endif /* __ASSEMBLY__ */
+#endif /* __ASSEMBLER__ */
 
 #endif /* CORTEX_A75_H */