mxser: remove stale comment

The comment mentions ISA removed long time ago. It also comments on
.driver_data pointing to above structures. That is not true either.
Remove that.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jeremy Kerr <jk@codeconstruct.com.au>
Link: https://lore.kernel.org/r/20240808103549.429349-3-jirislaby@kernel.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>