Btrfs: fix check on same raid type flag twice

Code checked for raid 5 flag in two else-if branches, so code would never be reached. Probably a copy-paste bug.
Signed-off-by: Henrik Nordvik <henrikno@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

fs/btrfs/disk-io.c

@@ -3258,7 +3258,7 @@ int btrfs_calc_num_tolerated_disk_barrier_failures(
 					    BTRFS_BLOCK_GROUP_RAID10)) {
 						num_tolerated_disk_barrier_failures = 1;
 					} else if (flags &
-						   BTRFS_BLOCK_GROUP_RAID5) {
+						   BTRFS_BLOCK_GROUP_RAID6) {
 						num_tolerated_disk_barrier_failures = 2;
 					}
 				}