Accept rtsp client without interleaved parameter

[fmcloudconsulting]

Fix #1510

[AlexxIT]

Your changes are incorrect. The client can come for UDP transport.

[fmcloudconsulting]

The existing code already expects TCP-only transport, so there is no regression with this PR?

[AlexxIT]

But it return 461 Unsupported transport error, so smart client can change UDP to TCP request. Many clients support this out of box.

[fmcloudconsulting]

Got the point. Should be fixed now.

[AlexxIT]

It's wrong again. Some clients don't send unicast word. I think only first prefix should be enough.

[fmcloudconsulting]

Fixed.
By the way, there was a typo between tr and transport variables, fixed!
I'll build & deploy on my side.

[felipecrs]

@fmcloudconsulting did the deploy on your side happened successfully? Is this PR working as expected?

[AlexxIT]

Thanks!

[fmcloudconsulting]

Hello,

After hours of effort we were unable to get Genetec to work in RTSP over TCP.
Only RTSP over UDP seemed possible.
So we used mediamtx as restream server.

However, the patch proposed here has been tested for other clients and worked well.
Thanks for merging!

[AlexxIT]

It seems that the patch is useless because of the initially bad software.
I was responding in the issue that sw is not implementing the RTSP specification correctly.

[AlexxIT]

https://github.com/AlexxIT/go2rtc/releases/tag/v1.9.9