Btrfs: make inode.c:compress_file_range() return void

Its return value is useless, its single caller ignores it and can't do
anything with it anyway, since it's a workqueue task and not the task
calling filemap_fdatawrite_range (writepages) nor filemap_fdatawait_range().
Failure is communicated to such functions via start and end of writeback
with the respective pages tagged with an error and AS_EIO flag set in the
inode's imapping.
Signed-off-by: NFilipe Manana <fdmanana@suse.com>
Signed-off-by: NChris Mason <clm@fb.com>

fs/btrfs/inode.c

@@ -382,7 +382,7 @@ static inline int inode_need_compress(struct inode *inode)
  * are written in the same order that the flusher thread sent them
  * down.
  */
-static noinline int compress_file_range(struct inode *inode,
+static noinline void compress_file_range(struct inode *inode,
 					struct page *locked_page,
 					u64 start, u64 end,
 					struct async_cow *async_cow,
@@ -620,8 +620,7 @@ static noinline int compress_file_range(struct inode *inode,
 		*num_added += 1;
 	}
 
-out:
-	return ret;
+	return;
 
 free_pages_out:
 	for (i = 0; i < nr_pages_ret; i++) {
@@ -629,8 +628,6 @@ static noinline int compress_file_range(struct inode *inode,
 		page_cache_release(pages[i]);
 	}
 	kfree(pages);
-
-	goto out;
 }
 
 static void free_async_extent_pages(struct async_extent *async_extent)