btrfs: Fixed dsize and last_off declarations

The return values of btrfs_item_offset_nr and btrfs_item_size_nr are of
type u32. To avoid mixing signed and unsigned integers we should also
declare dsize and last_off to be of type u32.

Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Alexandru Moise <00moses.alexander00@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 5f745ea..f553913 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -4940,8 +4940,8 @@
 {
 	struct extent_buffer *leaf;
 	struct btrfs_item *item;
-	int last_off;
-	int dsize = 0;
+	u32 last_off;
+	u32 dsize = 0;
 	int ret = 0;
 	int wret;
 	int i;