ARM: vfp: use -mfloat-abi=soft to build vfp

Distros are starting to ship with toolchains defaulting to
hardfloat. Using such a compiler to build the kernel fails
in the VFP directory with

arch/arm/vfp/entry.S:1:0: sorry, unimplemented: -mfloat-abi=hard and VFP

Adding -mfloat-abi=soft to the gcc command line fixes this.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

arch/arm/vfp/Makefile

@@ -7,7 +7,7 @@
 # ccflags-y := -DDEBUG
 # asflags-y := -DDEBUG
 
-KBUILD_AFLAGS	:=$(KBUILD_AFLAGS:-msoft-float=-Wa,-mfpu=softvfp+vfp)
+KBUILD_AFLAGS	:=$(KBUILD_AFLAGS:-msoft-float=-Wa,-mfpu=softvfp+vfp -mfloat-abi=soft)
 LDFLAGS		+=--no-warn-mismatch
 
 obj-y			+= vfp.o