res_pjsip_session: Set stream state on created streams for incoming SDP.

res_pjsip_session: Set stream state on created streams for incoming SDP.

A previous review, 13174, made a change whereby on an incoming offer SDP
the pending topology was initialized to the configured. This caused a problem
for bundle with WebRTC where bundle could reference a stream that did not
actually exist if the configuration had both audio and video but the
offer SDP only contained audio.

This change undoes that review and instead fixes the original problem it
sought to solve by setting the state of created streams based on the
contents of the offer SDP. This way the stream state is not inactive
until negotiation later completes.

ASTERISK-28659

Change-Id: Ic5ae5a86437d3e686ac5afd91d133cc916198355