Btrfs: fix em leak in find_first_block_group

We need to call free_extent_map() on the em we look up.

Signed-off-by: Josef Bacik <[email protected]>
Reviewed-by: Omar Sandoval <[email protected]>
Signed-off-by: David Sterba <[email protected]>
Signed-off-by: Chris Mason <[email protected]>

Author: Josef Bacik

fs/btrfs/extent-tree.c

@@ -9887,6 +9887,7 @@ static int find_first_block_group(struct btrfs_root *root,
 			} else {
 				ret = 0;
 			}
+			free_extent_map(em);
 			goto out;
 		}
 		path->slots[0]++;