WebRTC: Refine the negotiation about the h264 codec 42e01f

[winlinvip]

SRS always choose 42e01f first, which is Constrained(e0) Baseline(42) Level3.1(1f), but we should also choose all 42****, because all baseline codec should be accepted.

So we should refine the negotiation:

1. Accept 42e01f
2. Accept 42e0**
3. Accept 42****

Please refer to following documents for details:

https://github.com/ibc/h264-profile-level-id/blob/master/test/test.js
https://blog.csdn.net/epubcn/article/details/102802108