[PATCH] isicom, mxser MAINTAINERS update

I can maintain moxa and isicom char drivers, because I've rewritten them to
the new API.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>