btrfs-progs: zoned: fix memory leak in btrfs_sb_io()

In btrfs_sb_io(), blk_zone_report is used for getting information about
zones. But it is not freed if code goes in usual path. This patch frees
the variable just after it used.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: Sidong Yang <realwakka@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>

kernel-shared/zoned.c

@@ -552,6 +552,7 @@ size_t btrfs_sb_io(int fd, void *buf, off_t offset, int rw)
 	zones = (struct blk_zone *)(rep + 1);
 
 	ret = sb_log_location(fd, zones, rw, &mapped);
+	free(rep);
 	/*
 	 * Special case: no superblock found in the zones. This case happens
 	 * when initializing a file-system.