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: http://svn.asterisk.org/svn/asterisk/trunk@405369 f38db490-d61c-443f-a65b-d21fe96a405b