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/arm/board/juno/juno_common.c b/plat/arm/board/juno/juno_common.c
index 118c19a..98c5d3c 100644
--- a/plat/arm/board/juno/juno_common.c
+++ b/plat/arm/board/juno/juno_common.c
@@ -37,7 +37,7 @@
 	CSS_MAP_DEVICE,
 	SOC_CSS_MAP_DEVICE,
 	ARM_MAP_NS_DRAM1,
-#ifdef AARCH64
+#ifdef __aarch64__
 	ARM_MAP_DRAM2,
 #endif
 #ifdef SPD_tspd
@@ -74,7 +74,7 @@
 #endif
 #ifdef IMAGE_BL32
 const mmap_region_t plat_arm_mmap[] = {
-#ifdef AARCH32
+#ifndef __aarch64__
 	ARM_MAP_SHARED_RAM,
 #ifdef PLAT_ARM_MEM_PROT_ADDR
 	ARM_V2M_MAP_MEM_PROTECT,