Add support for H265 and AV1

[rom1v]

Add an option to select the video codec to use:

scrcpy --codec=h264  # default
scrcpy --codec=h265
scrcpy --codec=av1

Of course, these codecs only work if the device provides an encoder (recent devices should have H265, I don't know which devices support AV1 yet).

H264 is still the default, for two reasons:

• it is supported everywhere
• it is often encoded with a lower latency

Fixes #3092