AArch32: Add essential ARM platform and FVP support

This patch adds AArch32 support for FVP and implements common platform APIs
like `plat_get_my_stack`, `plat_set_my_stack`, `plat_my_core_cos` for AArch32.
Only Multi Processor(MP) implementations of these functions are considered in
this patch. The ARM Standard platform layer helpers are implemented for
AArch32 and the common makefiles are modified to cater for both AArch64 and
AArch32 builds. Compatibility with the deprecated platform API is not
supported for AArch32.

Change-Id: Iad228400613eec91abf731b49e21a15bcf2833ea
diff --git a/plat/common/plat_gicv3.c b/plat/common/plat_gicv3.c
index 249caf8..c961d62 100644
--- a/plat/common/plat_gicv3.c
+++ b/plat/common/plat_gicv3.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2016, ARM Limited and Contributors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
@@ -186,6 +186,11 @@
 #pragma weak plat_ic_acknowledge_interrupt
 #pragma weak plat_ic_end_of_interrupt
 
+/* In AArch32, the secure group1 interrupts are targeted to Secure PL1 */
+#ifdef AARCH32
+#define IS_IN_EL1()	IS_IN_SECURE()
+#endif
+
 /*
  * This function returns the highest priority pending interrupt at
  * the Interrupt controller