Blackfin: encode cpu-rev into uImage name

Encoding the cpu family name apparently confuses people when they try to
boot an image on a sub-variant, so encode the specific cpu name and the
silicon rev instead.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
diff --git a/arch/blackfin/Makefile b/arch/blackfin/Makefile
index 802ac5f..46f42b2 100644
--- a/arch/blackfin/Makefile
+++ b/arch/blackfin/Makefile
@@ -97,8 +97,11 @@
 rev-$(CONFIG_BF_REV_NONE) := none
 rev-$(CONFIG_BF_REV_ANY)  := any
 
-KBUILD_CFLAGS += -mcpu=$(cpu-y)-$(rev-y)
-KBUILD_AFLAGS += -mcpu=$(cpu-y)-$(rev-y)
+CPU_REV := $(cpu-y)-$(rev-y)
+export CPU_REV
+
+KBUILD_CFLAGS += -mcpu=$(CPU_REV)
+KBUILD_AFLAGS += -mcpu=$(CPU_REV)
 
 # - we utilize the silicon rev from the toolchain, so move it over to the checkflags
 CHECKFLAGS_SILICON = $(shell echo "" | $(CPP) $(KBUILD_CFLAGS) -dD - 2>/dev/null | awk '$$2 == "__SILICON_REVISION__" { print $$3 }')