ext4: remove duplicate remount check for JOURNAL_CHECKSUM change

rejection of, changing journal_checksum during remount.  One suffices.

While we're at it, remove old comment about the "check" option
which has been deprecated for some time now.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

fs/ext4/super.c

@@ -4850,9 +4850,6 @@ static int ext4_remount(struct super_block *sb, int *flags, char *data)
 	if (sbi->s_journal && sbi->s_journal->j_task->io_context)
 		journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
 
-	/*
-	 * Allow the "check" option to be passed as a remount option.
-	 */
 	if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
 		err = -EINVAL;
 		goto restore_opts;
@@ -4866,14 +4863,6 @@ static int ext4_remount(struct super_block *sb, int *flags, char *data)
 		goto restore_opts;
 	}
 
-	if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
-	    test_opt(sb, JOURNAL_CHECKSUM)) {
-		ext4_msg(sb, KERN_ERR, "changing journal_checksum "
-			 "during remount not supported");
-		err = -EINVAL;
-		goto restore_opts;
-	}
-
 	if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
 		if (test_opt2(sb, EXPLICIT_DELALLOC)) {
 			ext4_msg(sb, KERN_ERR, "can't mount with "