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/qemu/qemu_common.c b/plat/qemu/qemu_common.c
index aee8321..56bf953 100644
--- a/plat/qemu/qemu_common.c
+++ b/plat/qemu/qemu_common.c
@@ -132,11 +132,11 @@
 	}
 
 /* Define EL1 and EL3 variants of the function initialising the MMU */
-#ifdef AARCH32
-DEFINE_CONFIGURE_MMU_EL(svc_mon)
-#else
+#ifdef __aarch64__
 DEFINE_CONFIGURE_MMU_EL(el1)
 DEFINE_CONFIGURE_MMU_EL(el3)
+#else
+DEFINE_CONFIGURE_MMU_EL(svc_mon)
 #endif