toolchain: add coldfire support

Add support for m68k/coldfire. A gcc patch is required
to avoid gcc ICE.

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

arch/Config.in

@@ -94,7 +94,7 @@ config BR2_i386
 
 config BR2_m68k
 	bool "m68k"
-	select BR2_ARCH_HAS_MMU_MANDATORY
+	# MMU support is set by the subarchitecture file, arch/Config.in.m68k
 	help
 	  Motorola 68000 family microprocessor
 	  http://en.wikipedia.org/wiki/M68k

arch/Config.in.m68k

@@ -4,6 +4,14 @@ config BR2_ARCH
 config BR2_ENDIAN
 	default "BIG"
 
+# symbols used to distinguish between m68k and coldfire
+# for gcc multilib
+config BR2_m68k_m68k
+	bool
+
+config BR2_m68k_cf
+	bool
+
 # coldfire variants will be added later
 choice
 	prompt "Target CPU"
@@ -14,8 +22,20 @@ choice
 
 config BR2_m68k_68040
 	bool "68040"
+	select BR2_m68k_m68k
+	select BR2_ARCH_HAS_MMU_MANDATORY
+
+config BR2_m68k_cf5208
+	bool "5208"
+	select BR2_m68k_cf
+	select BR2_SOFT_FLOAT
 
 endchoice
 
 config BR2_GCC_TARGET_CPU
 	default "68040"		if BR2_m68k_68040
+	default "5208"		if BR2_m68k_cf5208
+
+config BR2_GCC_TARGET_ARCH
+	default "m68k"		if BR2_m68k_m68k
+	default "cf"		if BR2_m68k_cf