[PATCH v2] btrfs: zoned: Remove redundant initialization of to_add

[Jiapeng Chong <jiapeng.chong@linux.alibaba.com>]

to_add is being initialized to len but this is never read as
to_add is overwritten later on. Remove the redundant
initialization.

Cleans up the following clang-analyzer warning:

fs/btrfs/extent-tree.c:2769:8: warning: Value stored to 'to_add' during
its initialization is never read [clang-analyzer-deadcode.DeadStores].

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
---
Changes in v2:
  -"to_add" is define within the if (!global_rsv->full) branch.

 fs/btrfs/extent-tree.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index d89273c4b6b8..8e91adbf352e 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -2766,12 +2766,10 @@ static int unpin_extent_range(struct btrfs_fs_info *fs_info,
 		spin_unlock(&cache->lock);
 		if (!readonly && return_free_space &&
 		    global_rsv->space_info == space_info) {
-			u64 to_add = len;
-
 			spin_lock(&global_rsv->lock);
 			if (!global_rsv->full) {
-				to_add = min(len, global_rsv->size -
-					     global_rsv->reserved);
+				u64 to_add = min(len, global_rsv->size -
+						 global_rsv->reserved);
 				global_rsv->reserved += to_add;
 				btrfs_space_info_update_bytes_may_use(fs_info,
 						space_info, to_add);
-- 
2.20.1.7.g153144c