btrfs: add multi-statement protection to btrfs_set/clear_and_info macros

Multi-statement macros should be enclosed in do/while(0) block to make
their use safe in single statement if conditions. All current uses of
the macros are safe, so this change is for future protection.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/ctree.h

@@ -1279,18 +1279,18 @@ static inline u32 BTRFS_MAX_XATTR_SIZE(const struct btrfs_fs_info *info)
 					 BTRFS_MOUNT_##opt)
 
 #define btrfs_set_and_info(fs_info, opt, fmt, args...)			\
-{									\
+do {									\
 	if (!btrfs_test_opt(fs_info, opt))				\
 		btrfs_info(fs_info, fmt, ##args);			\
 	btrfs_set_opt(fs_info->mount_opt, opt);				\
-}
+} while (0)
 
 #define btrfs_clear_and_info(fs_info, opt, fmt, args...)		\
-{									\
+do {									\
 	if (btrfs_test_opt(fs_info, opt))				\
 		btrfs_info(fs_info, fmt, ##args);			\
 	btrfs_clear_opt(fs_info->mount_opt, opt);			\
-}
+} while (0)
 
 /*
  * Requests for changes that need to be done during transaction commit.