Btrfs: consolidate btrfs_error() to btrfs_std_error()

btrfs_error() and btrfs_std_error() does the same thing
and calls _btrfs_std_error(), so consolidate them together.
And the main motivation is that btrfs_error() is closely
named with btrfs_err(), one handles error action the other
is to log the error, so don't closely name them.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Suggested-by: David Sterba <dsterba@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 4484063..a86051e 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -4127,14 +4127,7 @@
 				  __LINE__, (errno));		\
 } while (0)
 
-#define btrfs_std_error(fs_info, errno)				\
-do {								\
-	if ((errno))						\
-		__btrfs_std_error((fs_info), __func__,		\
-				   __LINE__, (errno), NULL);	\
-} while (0)
-
-#define btrfs_error(fs_info, errno, fmt, args...)		\
+#define btrfs_std_error(fs_info, errno, fmt, args...)		\
 do {								\
 	__btrfs_std_error((fs_info), __func__, __LINE__,	\
 			  (errno), fmt, ##args);		\