mxs: fix SD-card image generation for OLinuXino boards

Fixes: mxs: add generic subtarget (64ef920)

Adding the generic target caused the TARGET_BOOTFS_PARTSIZE to stay
hidden for these boards, crashing the FAT filesystem creation.

Signed-off-by: Zoltan HERPAI <[email protected]>

target/linux/mxs/image/Config.in

@@ -1,6 +1,6 @@
 config TARGET_BOOTFS_PARTSIZE
 	int "Boot (SD Card) filesystem partition size (in MB)"
-	depends on TARGET_mxs_olinuxino-maxi || TARGET_mxs_olinuxino-micro
+	depends on TARGET_mxs_generic_olinuxino-maxi || TARGET_mxs_generic_olinuxino-micro
 	default 8
 	help
 	    On the Olimex OLinuXino boards, mainline U-Boot loads the