MAINTAINERS: Remove 1.2 from the maintained releases

The only distribution which still uses it according to
https://trac.ffmpeg.org/wiki/Downstreams is "gentoo stable", but
http://packages.gentoo.org/package/media-video/ffmpeg lists stable as shipping 1.2.6 which is 6 point
releases behind. Also gentoos ffmpeg maintainer stated "don't worry about gentoo: we're in the process
of moving to latest 2.2 for stable."

CC: Alexis Ballier <aballier@gentoo.org>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

MAINTAINERS

@@ -548,7 +548,6 @@ Releases
 2.5                                     Michael Niedermayer
 2.4                                     Michael Niedermayer
 2.2                                     Michael Niedermayer
-1.2                                     Michael Niedermayer
 
 If you want to maintain an older release, please contact us