Exact Frame Rate SDP Field for SMPTE 291 SDP Generation

[cmaberto]

Seems like the exactframerate SDP field is not correctly written. Seems like the if statement for checking for exactframerate is incorrect in make_video_smpte291_sdp_parameters. Removing the not seemed to have fixed me issues with it, unless I am using the functions wrong for 2110-40 SDP creation.

[garethsb]

Thank you, @cmaberto, your fix is good. The exactframerate is already added correctly for video/raw but the not is wrong in the code for video/smpte291 here:

nmos-cpp/Development/nmos/sdp_utils.cpp

Line 836 in 9ebb3ae

if (!params.exactframerate) fmtp.push_back({ sdp::fields::exactframerate, nmos::details::make_exactframerate(params.exactframerate) });

SDP test cases should be increased for ST 2110-40.

[jonathan-r-thorpe]

Resolved by #346