fs/ext2: fix double quoted label

fs/ext2: fix double quoted label

Since the commit 6dd7bbb59134799ed3d7343f238b3b02592faebf, the label does
not need anymore to be quoted. Even worse it *must* not be simple-quoted,
unless the label will contain the double-quotes from the config variable
BR2_TARGET_ROOTFS_EXT2_LABEL.

The commit mentionned above has replaced echo by printf:
-	echo "$$(ROOTFS_$(2)_CMD)" >> $$(FAKEROOT_SCRIPT)
+	$$(call PRINTF,$$(ROOTFS_$(2)_CMD)) >> $$(FAKEROOT_SCRIPT)

Since this commit the rootfs label contains extra double-quotes.
$ blkid
/dev/mmcblk0: LABEL=""BR 2016.08"" UUID="xxx"
                     ^          ^

With this fix, the extra double-quotes have disappeared:
/dev/mmcblk0: LABEL="BR 2016.11-rc2" UUID="yyy"

Signed-off-by: Gaël PORTAY <gael.portay@savoirfairelinux.com>
Acked-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>