btrfs: use unsigned type for single bit bitfield

Signed-off-by: David Sterba <dsterba@suse.cz>

fs/btrfs/ctree.h

@@ -740,12 +740,12 @@ struct btrfs_space_info {
 	 */
 	unsigned long reservation_progress;
 
-	int full:1;		/* indicates that we cannot allocate any more
+	unsigned int full:1;	/* indicates that we cannot allocate any more
 				   chunks for this space */
-	int chunk_alloc:1;	/* set if we are allocating a chunk */
+	unsigned int chunk_alloc:1;	/* set if we are allocating a chunk */
 
-	int force_alloc;	/* set if we need to force a chunk alloc for
+	unsigned int force_alloc;	/* set if we need to force a chunk
-				   this space */
+					   alloc for this space */
 
 	struct list_head list;