bfin: change default to bf532, internal toolchain !bf6xx

The default Blackfin processor in Buildroot isn't supported by
gcc 6.1.0, so use bf532 as default. Disable any bf6xx processors
for internal toolchain users.

Signed-off-by: Waldemar Brodkorb <wbx@openadk.org>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

arch/Config.in.bfin

@@ -1,7 +1,7 @@
 choice
 	prompt "Target CPU"
 	depends on BR2_bfin
-	default BR2_bf609
+	default BR2_bf532
 	help
 	  Specify target CPU
 config BR2_bf606

toolchain/Config.in

@@ -42,6 +42,10 @@ choice
 config BR2_TOOLCHAIN_BUILDROOT
 	bool "Buildroot toolchain"
 	select BR2_TOOLCHAIN_HAS_SHADOW_PASSWORDS
+	depends on !BR2_bf606
+	depends on !BR2_bf607
+	depends on !BR2_bf608
+	depends on !BR2_bf609
 
 config BR2_TOOLCHAIN_EXTERNAL
 	bool "External toolchain"