res_format_attr_h264.c: Make sure profile-level-id fmtp attribute is set

The profile-iop octet (the 2nd) of profile-level-id can be zero
according to RFC 6184 Section 8.1. So we ignore its value when deciding
to include profile-level-id in the outgoing SDP.

ASTERISK-27959 #close
Reported by: David Kuehling

Change-Id: Id28cd916a3d7748058fe9609b585d07d9e243f73