chan_sip: Always use fromdomain if set for domain, even if callerid is set to restricted.

(closes issue ASTERISK-20841)
Reported by: Kelly Goedert
........

Merged revisions 411021 from http://svn.asterisk.org/svn/asterisk/branches/1.8


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/11@411022 65c4cc65-6c06-0410-ace0-fbb531ad65f3