Make xcompile support multiple architectures

With this change the the xcompile script now creates environment variables
for more than one architecture.

Signed-off-by: David Hendricks <dhendrix@chromium.org>
Signed-off-by: Hung-Te Lin <hungte@chromium.org>
Signed-off-by: Stefan Reinauer <stepan@coresystems.de>

Change-Id: I349a1fd1d865ef16979f1dfd6aeca12b1ee2eed6
Signed-off-by: Ronald G. Minnich <rminnich@gmail.com>
Reviewed-on: http://review.coreboot.org/1915
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Tested-by: build bot (Jenkins)

Makefile

@@ -78,7 +78,6 @@ HOSTCC = gcc
 HOSTCXX = g++
 HOSTCFLAGS := -g
 HOSTCXXFLAGS := -g
-LIBGCC_FILE_NAME := $(shell test -r `$(CC) -print-libgcc-file-name` && $(CC) -print-libgcc-file-name)
 
 DOXYGEN := doxygen
 DOXYGEN_OUTPUT_DIR := doxygen
@@ -114,6 +113,31 @@ else
 
 include $(HAVE_DOTCONFIG)
 
+ARCHDIR-$(CONFIG_ARCH_ARM)     := armv7
+ARCHDIR-$(CONFIG_ARCH_X86)     := x86
+
+ARCH-y := $(ARCHDIR-y)
+
+# If architecture folder name is different from GCC binutils architecture name,
+# override here.
+ARCH-$(CONFIG_ARCH_ARM)     := littlearm
+ARCH-$(CONFIG_ARCH_X86)     := i386
+
+CC := $(CC_$(ARCH-y))
+AS := $(AS_$(ARCH-y))
+LD := $(LD_$(ARCH-y))
+NM := $(NM_$(ARCH-y))
+OBJCOPY := $(OBJCOPY_$(ARCH-y))
+OBJDUMP := $(OBJDUMP_$(ARCH-y))
+READELF := $(READELF_$(ARCH-y))
+STRIP := $(STRIP_$(ARCH-y))
+AR := $(AR_$(ARCH-y))
+
+CFLAGS += $(CFLAGS_$(ARCH-y))
+
+LIBGCC_FILE_NAME := $(shell test -r `$(CC) -print-libgcc-file-name` && \
+		      $(CC) -print-libgcc-file-name)
+
 ifneq ($(INNER_SCANBUILD),y)
 ifeq ($(CONFIG_COMPILER_LLVM_CLANG),y)
 CC:=clang -m32 -mno-mmx -mno-sse