ext4: remove unused return value of ext4_mb_try_best_found and ext4_mb_free_metadata

Return value static function ext4_mb_try_best_found and
ext4_mb_free_metadata is not used. Just remove unused return value.
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://lore.kernel.org/r/20230303172120.3800725-9-shikemeng@huaweicloud.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

fs/ext4/mballoc.c

@@ -2124,7 +2124,7 @@ static void ext4_mb_measure_extent(struct ext4_allocation_context *ac,
 }
 
 static noinline_for_stack
-int ext4_mb_try_best_found(struct ext4_allocation_context *ac,
+void ext4_mb_try_best_found(struct ext4_allocation_context *ac,
 					struct ext4_buddy *e4b)
 {
 	struct ext4_free_extent ex = ac->ac_b_ex;
@@ -2135,7 +2135,7 @@ int ext4_mb_try_best_found(struct ext4_allocation_context *ac,
 	BUG_ON(ex.fe_len <= 0);
 	err = ext4_mb_load_buddy(ac->ac_sb, group, e4b);
 	if (err)
-		return err;
+		return;
 
 	ext4_lock_group(ac->ac_sb, group);
 	max = mb_find_extent(e4b, ex.fe_start, ex.fe_len, &ex);
@@ -2147,8 +2147,6 @@ int ext4_mb_try_best_found(struct ext4_allocation_context *ac,
 
 	ext4_unlock_group(ac->ac_sb, group);
 	ext4_mb_unload_buddy(e4b);
-
-	return 0;
 }
 
 static noinline_for_stack
@@ -5700,7 +5698,7 @@ static void ext4_try_merge_freed_extent(struct ext4_sb_info *sbi,
 	kmem_cache_free(ext4_free_data_cachep, entry);
 }
 
-static noinline_for_stack int
+static noinline_for_stack void
 ext4_mb_free_metadata(handle_t *handle, struct ext4_buddy *e4b,
 		      struct ext4_free_data *new_entry)
 {
@@ -5743,7 +5741,7 @@ ext4_mb_free_metadata(handle_t *handle, struct ext4_buddy *e4b,
 				EXT4_C2B(sbi, cluster),
 				"Block already on to-be-freed list");
 			kmem_cache_free(ext4_free_data_cachep, new_entry);
-			return 0;
+			return;
 		}
 	}
 
@@ -5769,7 +5767,6 @@ ext4_mb_free_metadata(handle_t *handle, struct ext4_buddy *e4b,
 	list_add_tail(&new_entry->efd_list, &sbi->s_freed_data_list);
 	sbi->s_mb_free_pending += clusters;
 	spin_unlock(&sbi->s_md_lock);
-	return 0;
 }
 
 /*