Downgrade build message from makefile from error to warning for arm-embedded. This makes it possible to build a working RTL with external startup code for subarchs with no cpu units.

git-svn-id: trunk@32750 -

rtl/embedded/Makefile

@@ -374,7 +374,7 @@ ifeq ($(SUBARCH),armv7a)
 CPU_UNITS=allwinner_a20
 endif
 ifeq ($(CPU_UNITS),)
-$(error Invalid value set for SUBARCH)
+$(warning No CPUs enabled for given SUBARCH)
 endif
 endif
 ifeq ($(ARCH),avr)

rtl/embedded/Makefile.fpc

@@ -82,7 +82,7 @@ ifeq ($(SUBARCH),armv7a)
 CPU_UNITS=allwinner_a20
 endif
 ifeq ($(CPU_UNITS),)
-$(error Invalid value set for SUBARCH)
+$(warning No CPUs enabled for given SUBARCH)
 endif
 endif