ubifs: Allow ubifsmount volume reference by number

UBI can mount volumes by name or number  The current code forces you
to name the volume by prepending every name with "ubi:".

>From fs/ubifs/super.c
 * There are several ways to specify UBI volumes when mounting UBIFS:
 * o ubiX_Y    - UBI device number X, volume Y;
 * o ubiY      - UBI device number 0, volume Y;
 * o ubiX:NAME - mount UBI device X, volume with name NAME;
 * o ubi:NAME  - mount UBI device 0, volume with name NAME.

Now any name passed in any of the above forms are allowed.

Also update the configs that referenced ubifsmount.

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>
diff --git a/include/configs/cam_enc_4xx.h b/include/configs/cam_enc_4xx.h
index a7a698c..56528dd 100644
--- a/include/configs/cam_enc_4xx.h
+++ b/include/configs/cam_enc_4xx.h
@@ -451,7 +451,7 @@
 	"bootfile=" __stringify(CONFIG_HOSTNAME) "/uImage \0"		\
 	"kernel_addr_r=80600000\0"					\
 	"load_kernel=tftp ${kernel_addr_r} ${bootfile}\0"		\
-	"ubi_load_kernel=ubi part ubi 2048;ubifsmount ${img_volume};"	\
+	"ubi_load_kernel=ubi part ubi 2048;ubifsmount ubi:${img_volume};" \
 		"ubifsload ${kernel_addr_r} boot/uImage\0"		\
 	"fit_addr_r=" __stringify(CONFIG_BOARD_IMG_ADDR_R) "\0"		\
 	"img_addr_r=" __stringify(CONFIG_BOARD_IMG_ADDR_R) "\0"		\