[PATCH] btrfs: Fix -Wmaybe-uninitialized warning

[Qiang Ma <maqianga@uniontech.com>]

Fix a -Wmaybe-uninitialized warning by initializing
the variable to NULL.

$ make CFLAGS_tree-log.o=-Wmaybe-uninitialized

In file included from fs/btrfs/ctree.h:21,
                 from fs/btrfs/tree-log.c:12:
fs/btrfs/accessors.h: In function 'replay_one_buffer':
fs/btrfs/accessors.h:66:16: warning: 'inode_item' may be used uninitialized [-Wmaybe-uninitialized]
   66 |         return btrfs_get_##bits(eb, s, offsetof(type, member));         \
      |                ^~~~~~~~~~
fs/btrfs/tree-log.c:2803:42: note: 'inode_item' declared here
 2803 |                 struct btrfs_inode_item *inode_item;
      |                                          ^~~~~~~~~~

Warning was found when compiling using loongarch64-gcc 12.3.1.

Signed-off-by: Qiang Ma <maqianga@uniontech.com>
---
 fs/btrfs/tree-log.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 31edc93a383e..0d6faaaa70f1 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -2798,7 +2798,7 @@ static int replay_one_buffer(struct extent_buffer *eb,
 
 	nritems = btrfs_header_nritems(eb);
 	for (wc->log_slot = 0; wc->log_slot < nritems; wc->log_slot++) {
-		struct btrfs_inode_item *inode_item;
+		struct btrfs_inode_item *inode_item = NULL;
 
 		btrfs_item_key_to_cpu(eb, &wc->log_key, wc->log_slot);
 
-- 
2.20.1