Skinny: do not add call to missed calls list if answered elsewhere.

Patch updates skinny devices with a SKINNY_CONNECTED callstate if an
inbound ringing or callwaiting call is answered elsewhere.
........

Merged revisions 405367 from http://svn.asterisk.org/svn/asterisk/branches/12


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@405369 65c4cc65-6c06-0410-ace0-fbb531ad65f3