kbuild: Enable -fshort-wchar

EFI_LOADER really wants UTF-16 strings (ie. %ls and L"string" are 16bit
chars instead of 32bit chars).  But rather than enabling -fshort-wchar
conditionally if EFI_LOADER is enabled, it was deemed preferrable to
globally switch.

Signed-off-by: Rob Clark <robdclark@gmail.com>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Makefile

@@ -360,6 +360,7 @@ KBUILD_CPPFLAGS := -D__KERNEL__ -D__UBOOT__
 KBUILD_CFLAGS   := -Wall -Wstrict-prototypes \
 		   -Wno-format-security \
 		   -fno-builtin -ffreestanding
+KBUILD_CFLAGS	+= -fshort-wchar
 KBUILD_AFLAGS   := -D__ASSEMBLY__
 
 # Read UBOOTRELEASE from include/config/uboot.release (if it exists)