Fix for block device detection

Author: dougalb

bootstrap/src/scripts/boot_as_master

@@ -65,7 +65,7 @@ while [ $TRY -lt 3 ]; do
   fi
 done
 dev=$(stat /dev/disk/by-ebs-volumeid/${cfn_volume}|grep -- 'File:'|awk '{print $4}'|cut -d'/' -f3|tr -d "'")
-fs_type=$(blkid -o list | grep -- "$dev" | awk '{print $2}')
+fs_type=$(blkid -o list /dev/$dev | grep -- "$dev" | awk '{print $2}')
 if [ "${fs_type}x" == "x" ]; then
   mkfs.xfs /dev/disk/by-ebs-volumeid/${cfn_volume} || RC=1
   sleep 5