btrfs: zoned: make btrfs_get_dev_zone() static

It's not used outside zoned.c, so make it static.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/zoned.c

@@ -652,8 +652,7 @@ struct btrfs_zoned_device_info *btrfs_clone_dev_zone_info(struct btrfs_device *o
 	return NULL;
 }
 
-int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
-		       struct blk_zone *zone)
+static int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos, struct blk_zone *zone)
 {
 	unsigned int nr_zones = 1;
 	int ret;

fs/btrfs/zoned.h

@@ -53,8 +53,6 @@ struct btrfs_zoned_device_info {
 void btrfs_finish_ordered_zoned(struct btrfs_ordered_extent *ordered);
 
 #ifdef CONFIG_BLK_DEV_ZONED
-int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
-		       struct blk_zone *zone);
 int btrfs_get_dev_zone_info_all_devices(struct btrfs_fs_info *fs_info);
 int btrfs_get_dev_zone_info(struct btrfs_device *device, bool populate_cache);
 void btrfs_destroy_dev_zone_info(struct btrfs_device *device);
@@ -98,11 +96,6 @@ int btrfs_zoned_activate_one_bg(struct btrfs_fs_info *fs_info,
 				struct btrfs_space_info *space_info, bool do_finish);
 void btrfs_check_active_zone_reservation(struct btrfs_fs_info *fs_info);
 #else /* CONFIG_BLK_DEV_ZONED */
-static inline int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
-				     struct blk_zone *zone)
-{
-	return 0;
-}
 
 static inline int btrfs_get_dev_zone_info_all_devices(struct btrfs_fs_info *fs_info)
 {