Blackfin arch: Add proper -mcpu option according to the cpu and silicon revision configuration

Add silicon revision "any" and "none". Add proper -mcpu option according
to the cpu and silicon revision configuration.

Need update to use latest Blackfin cross compile toolchain.

Signed-off-by: Jie Zhang <jie.zhang@analog.com>
Signed-off-by: Mike Frysinger <michael.frysinger@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>

diff --git a/arch/blackfin/Kconfig b/arch/blackfin/Kconfig
index 1fad856..d98bafc 100644
--- a/arch/blackfin/Kconfig
+++ b/arch/blackfin/Kconfig
@@ -142,6 +142,12 @@
 	bool "0.5"
 	depends on (BF561 || BF533 || BF532 || BF531)
 
+config BF_REV_ANY
+	bool "any"
+
+config BF_REV_NONE
+	bool "none"
+
 endchoice
 
 config BFIN_DUAL_CORE