devpts: Remove sync_filesystems

devpts does not and never will have anything to sync
so don't bother calling sync_filesystems on remount.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

fs/devpts/inode.c

@@ -336,7 +336,6 @@ static int devpts_remount(struct super_block *sb, int *flags, char *data)
 	struct pts_fs_info *fsi = DEVPTS_SB(sb);
 	struct pts_mount_opts *opts = &fsi->mount_opts;
 
-	sync_filesystem(sb);
 	err = parse_mount_options(data, PARSE_REMOUNT, opts);
 
 	/*