Switch AARCH32/AARCH64 to __aarch64__

NOTE: AARCH32/AARCH64 macros are now deprecated in favor of __aarch64__.

All common C compilers pre-define the same macros to signal which
architecture the code is being compiled for: __arm__ for AArch32 (or
earlier versions) and __aarch64__ for AArch64. There's no need for TF-A
to define its own custom macros for this. In order to unify code with
the export headers (which use __aarch64__ to avoid another dependency),
let's deprecate the AARCH32 and AARCH64 macros and switch the code base
over to the pre-defined standard macro. (Since it is somewhat
unintuitive that __arm__ only means AArch32, let's standardize on only
using __aarch64__.)

Change-Id: Ic77de4b052297d77f38fc95f95f65a8ee70cf200
Signed-off-by: Julius Werner <jwerner@chromium.org>
diff --git a/plat/hisilicon/poplar/bl2_plat_setup.c b/plat/hisilicon/poplar/bl2_plat_setup.c
index 11403b0..cc9d975 100644
--- a/plat/hisilicon/poplar/bl2_plat_setup.c
+++ b/plat/hisilicon/poplar/bl2_plat_setup.c
@@ -54,7 +54,7 @@
 /*******************************************************************************
  * Gets SPSR for BL33 entry
  ******************************************************************************/
-#ifndef AARCH32
+#ifdef __aarch64__
 uint32_t poplar_get_spsr_for_bl33_entry(void)
 {
 	unsigned long el_status;
@@ -93,7 +93,7 @@
 			SPSR_E_LITTLE, DISABLE_ALL_EXCEPTIONS);
 	return spsr;
 }
-#endif /* AARCH32 */
+#endif /* __aarch64__ */
 
 int poplar_bl2_handle_post_image_load(unsigned int image_id)
 {
@@ -107,7 +107,7 @@
 	assert(bl_mem_params);
 
 	switch (image_id) {
-#ifdef AARCH64
+#ifdef __aarch64__
 	case BL32_IMAGE_ID:
 #ifdef SPD_opteed
 		pager_mem_params = get_bl_mem_params_node(BL32_EXTRA1_IMAGE_ID);