Fix EXTENT_MAP_INLINE off by one in btrfs_drop_extents

Don't set hint_byte to EXTENT_MAP_INLINE when 'end == extent_end' or
'start == key.offset' . The inline extent will be truncated in these
cases.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

fs/btrfs/file.c

@@ -475,8 +475,7 @@ int btrfs_drop_extents(struct btrfs_trans_handle *trans,
 			search_start = (extent_end + mask) & ~mask;
 		} else
 			search_start = extent_end;
-
-		if (end <= extent_end && start >= key.offset && found_inline) {
+		if (end < extent_end && start > key.offset && found_inline) {
 			*hint_byte = EXTENT_MAP_INLINE;
 		}
 		if (end < extent_end && end >= key.offset) {