feat(msm8916): add SP_MIN port for AArch32

Use the new shared msm8916 setup code to allow compiling the minimal
AArch32 Secure Payload (SP_MIN) as simple PSCI implementation.

AArch64 is preferred for the Cortex-A53 cores in MSM8916 but there are
some similar platforms with AArch32-only Cortex-A7 cores that can
benefit from this in future changes.

The AArch32 assembly implementation for msm8916_helpers.S and
uartdm_console.S is a direct port of the AArch64 implementation.
Only plat_get_my_entrypoint is slightly different because there is no
need to handle the "boot remapper" on cold boot for AArch32.

Change-Id: Idf160e86fb3e685fcedec3e051400e6273997b74
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
diff --git a/plat/qti/msm8916/platform.mk b/plat/qti/msm8916/platform.mk
index b3ea2fe..4dce773 100644
--- a/plat/qti/msm8916/platform.mk
+++ b/plat/qti/msm8916/platform.mk
@@ -27,8 +27,12 @@
 BL31_SOURCES		+=	${MSM8916_PM_SOURCES}				\
 				plat/qti/msm8916/msm8916_bl31_setup.c
 
-PLAT_INCLUDES		:=	-Iinclude/plat/arm/common/${ARCH}		\
-				-Iplat/qti/msm8916/include
+PLAT_INCLUDES		:=	-Iplat/qti/msm8916/include
+
+ifeq (${ARCH},aarch64)
+# arm_macros.S exists only on aarch64 currently
+PLAT_INCLUDES		+=	-Iinclude/plat/arm/common/${ARCH}
+endif
 
 # Only BL31 is supported at the moment and is entered on a single CPU
 RESET_TO_BL31			:= 1
@@ -62,8 +66,13 @@
 # Build config flags
 # ------------------
 BL31_BASE			?= 0x86500000
-BL32_BASE			?= BL31_LIMIT
 PRELOADED_BL33_BASE		?= 0x8f600000
 
+ifeq (${ARCH},aarch64)
+BL32_BASE			?= BL31_LIMIT
 $(eval $(call add_define,BL31_BASE))
+else
+# There is no BL31 on aarch32, so reuse its location for BL32
+BL32_BASE			?= $(BL31_BASE)
+endif
 $(eval $(call add_define,BL32_BASE))