build: Config-images: fix unit of partition sizes

The code interprets these config values as Mebibytes rather than
Megabytes so modify the description accordingly.

Signed-off-by: Paul Fertser <[email protected]>
[fix commit title prefix]
Signed-off-by: Adrian Schmutzler <[email protected]>

config/Config-images.in

@@ -280,14 +280,14 @@ menu "Target Images"
 	source "target/linux/*/image/Config.in"
 
 	config TARGET_KERNEL_PARTSIZE
-		int "Kernel partition size (in MB)"
+		int "Kernel partition size (in MiB)"
 		depends on USES_BOOT_PART
 		default 8 if TARGET_apm821xx_sata
 		default 64 if TARGET_bcm27xx
 		default 16
 
 	config TARGET_ROOTFS_PARTSIZE
-		int "Root filesystem partition size (in MB)"
+		int "Root filesystem partition size (in MiB)"
 		depends on USES_ROOTFS_PART || TARGET_ROOTFS_EXT4FS || TARGET_omap || TARGET_sunxi || TARGET_uml
 		default 104
 		help