channels/chan_sip: Clarify WARNING message in mismatched SRTP scenario

channels/chan_sip: Clarify WARNING message in mismatched SRTP scenario

When we receive an SDP as part of an offer/answer for a peer/friend has been
configured to require encryption, and that SDP offer/answer failed to provide
acceptable crypto attributes, we currently issue a WARNING that uses the phrase
"we" and "requested". In this case, both of those terms are ambiguous - the
user will probably think "we" is Asterisk (it most likely isn't) and it may
not be a "request", so much as an SDP that was received in some fashion.

This patch makes the WARNING messages slightly less bad and a bit more
accurate as well.

ASTERISK-23214 #close
Reported by: Rusty Newton
........

Merged revisions 432277 from http://svn.asterisk.org/svn/asterisk/branches/11

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/13@432278 65c4cc65-6c06-0410-ace0-fbb531ad65f3