btrfs: cleanup: remove no-used alloc_chunk in btrfs_check_data_free_space()

int alloc_chunk is never used in this function, remove it.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>

fs/btrfs/extent-tree.c

@@ -3599,7 +3599,7 @@ int btrfs_check_data_free_space(struct inode *inode, u64 bytes)
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct btrfs_fs_info *fs_info = root->fs_info;
 	u64 used;
-	int ret = 0, committed = 0, alloc_chunk = 1;
+	int ret = 0, committed = 0;
 
 	/* make sure bytes are sectorsize aligned */
 	bytes = ALIGN(bytes, root->sectorsize);
@@ -3627,7 +3627,7 @@ int btrfs_check_data_free_space(struct inode *inode, u64 bytes)
 		 * if we don't have enough free bytes in this space then we need
 		 * to alloc a new chunk.
 		 */
-		if (!data_sinfo->full && alloc_chunk) {
+		if (!data_sinfo->full) {
 			u64 alloc_target;
 
 			data_sinfo->force_alloc = CHUNK_ALLOC_FORCE;