DB410c: fix installer image

The GUI installer expects the images to be installed to be places on a VFAT
partition (so that images can be copy/pasted from any PC for example). So we
need to ensure that we mount this partition at boot.

Also disabling rootfs resize , since it's a waste of time in this case.

Change-Id: I1aae7b95c97d26ebd8f1341ca46a5774394e7cf1
Signed-off-by: Nicolas Dechesne <nicolas.dechesne@linaro.org>
diff --git a/scripts/DB410C/21-customize b/scripts/DB410C/21-customize
index 8bba4a0..bf49739 100755
--- a/scripts/DB410C/21-customize
+++ b/scripts/DB410C/21-customize
@@ -12,6 +12,16 @@
 /dev/disk/by-partlabel/rootfs / ext4   rw,relatime,data=ordered 0 1
 EOF
 
+if ifclass INSTALLER; then
+    # no need to resize rootfs for SD card boot
+    rm -f $target/lib/systemd/system/resize-helper.service
+
+    # needed by GUI installer
+    cat << EOF >> $target/etc/fstab
+/dev/mmcblk1p9 /mnt vfat defaults 0 0
+EOF
+fi
+
 # In case initrd doesn't exist, create it, else update
 if [ -f $target/boot/initrd.img-${KVERS} ]
 then