bcachefs: fix incorrect i_state usage

Reported-by: syzbot+95e40eae71609e40d851@syzkaller.appspotmail.com
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

fs/bcachefs/fs.c

@@ -193,7 +193,7 @@ static struct bch_inode_info *bch2_inode_insert(struct bch_fs *c, struct bch_ino
 		 * only insert fully created inodes in the inode hash table. But
 		 * discard_new_inode() expects it to be set...
 		 */
-		inode->v.i_flags |= I_NEW;
+		inode->v.i_state |= I_NEW;
 		/*
 		 * We don't want bch2_evict_inode() to delete the inode on disk,
 		 * we just raced and had another inode in cache. Normally new