fs: Kconfig: Add a separate option for FS_CRAMFS

Rather than using CMD_CRAMFS for both the filesystem and its command, we
should have a separate option for each. This allows us to enable CRAMFS
support without the command, if desired, which reduces U-Boot's size
slightly.

Signed-off-by: Simon Glass <sjg@chromium.org>
[trini: imply FS_CRAMFS for keymile]
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/UCP1020_SPIFLASH_defconfig b/configs/UCP1020_SPIFLASH_defconfig
index 4e5e0c1..2b3e4bd 100644
--- a/configs/UCP1020_SPIFLASH_defconfig
+++ b/configs/UCP1020_SPIFLASH_defconfig
@@ -34,4 +34,5 @@
 CONFIG_FSL_ESPI=y
 CONFIG_USB=y
 CONFIG_USB_STORAGE=y
+CONFIG_FS_CRAMFS=y
 CONFIG_OF_LIBFDT=y