make crossgcc: compile all required toolchains

The ARMv7 toolchain is now also needed for abuild (at least
if you want to be able to compile ARM images)

Change-Id: If1253203a2198f7dea632ba45540222ba3361932
Signed-off-by: Stefan Reinauer <reinauer@google.com>
Reviewed-on: http://review.coreboot.org/2147
Tested-by: build bot (Jenkins)
Reviewed-by: Marc Jones <marcj303@gmail.com>

util/crossgcc/Makefile

@@ -1,11 +1,13 @@
 all: build
 
 build:
-	bash ./buildgcc -G
+	bash ./buildgcc -G -p i386-elf
+	bash ./buildgcc -G -p armv7a-eabi
 
 .PHONY: build-without-gdb
 build-without-gdb:
-	bash ./buildgcc
+	bash ./buildgcc -p i386-elf
+	bash ./buildgcc -p armv7a-eabi
 
 clean:
 	rm -rf xgcc