btrfs: replace unnecessary goto with direct return at cow_file_range()

The 'goto out' in cow_file_range() in the exit block are not necessary
and jump back. Replace them with return, while still keeping 'goto out'
in the main code.
Reviewed-by: NFilipe Manana <fdmanana@suse.com>
Signed-off-by: NNaohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
[ keep goto in the main code, update changelog ]
Signed-off-by: NDavid Sterba <dsterba@suse.com>

fs/btrfs/inode.c

@@ -1413,7 +1413,7 @@ static noinline int cow_file_range(struct btrfs_inode *inode,
 					     page_ops);
 		start += cur_alloc_size;
 		if (start >= end)
-			goto out;
+			return ret;
 	}
 
 	/*
@@ -1425,7 +1425,7 @@ static noinline int cow_file_range(struct btrfs_inode *inode,
 	extent_clear_unlock_delalloc(inode, start, end, locked_page,
 				     clear_bits | EXTENT_CLEAR_DATA_RESV,
 				     page_ops);
-	goto out;
+	return ret;
 }
 
 /*