MAINTAINERS: Add dashenc maintainer

If somebody else wants to maintain dashenc either now or in future,
I am absolutely fine with giving up this responsibility anytime.
But till then we need a maintainer for dashenc, and I am volunteering for that task.
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

MAINTAINERS

@@ -395,6 +395,7 @@ Muxers/Demuxers:
   cdxl.c                                Paul B Mahol
   crc.c                                 Michael Niedermayer
   dashdec.c                             Steven Liu
+  dashenc.c                             Karthick Jeyapal
   daud.c                                Reimar Doeffinger
   dss.c                                 Oleksij Rempel
   dtsdec.c                              foo86