spl: Kconfig: Replace CONFIG_SPL_FAT_SUPPORT with CONFIG_SPL_FS_FAT

Replace CONFIG_SPL_FAT_SUPPORT with CONFIG_SPL_FS_FAT so
obj-$(CONFIG_$(SPL_)FS_FAT) can be used to control the build in both
SPL and U-Boot.

Signed-off-by: Tien Fong Chee <tien.fong.chee@intel.com>
Reviewed-by: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/arch/arm/mach-zynq/Kconfig b/arch/arm/mach-zynq/Kconfig
index 21dfebf..79f831e 100644
--- a/arch/arm/mach-zynq/Kconfig
+++ b/arch/arm/mach-zynq/Kconfig
@@ -3,7 +3,7 @@
 config SPL_LDSCRIPT
 	default "arch/arm/mach-zynq/u-boot-spl.lds"
 
-config SPL_FAT_SUPPORT
+config SPL_FS_FAT
 	default y
 
 config SPL_LIBCOMMON_SUPPORT