Log Message:
openh264: update to 2.6.0.

v2.6.0
------
- Initialize PSNR to 0 instead of NAN (Commit: cf3b514b, PR: #3836)
- Enable PIC in x86 assembly code (Commit: c42fa040, PR: #3831)
- Add QEMU test for LoongArch architecture (Commit: e49c0953, PR: #3833)
- Add support for calculating PSNR for Y/U/V components (Commit: 33f7f486, PR: #3824)
- Add support for PowerPC architecture in meson.build (Commit: 423eb2c3, PR: #3806)
- Fix potential bug in the codebase (Commit: 63db555e, PR: #3818)
- Pass the actual temporal ID to GMPVideoEncodedFrame (Commit: 1c47e719, PR: #3828)
- Use HW_NCPUONLINE on OpenBSD / NetBSD for CPU detection (Commit: fc1605c1, PR: \ 
#3813)
- Add Windows VSBuildTools VC17 compile support (Commit: 1ebb3f1a, PR: #3823)
- Expose temporal layer info via GMP API at encoder initialization and on a \ 
per-frame basis (Commit: ad3f6904, PR: #3821)
- Remove the use of -Werror to prevent warnings from being treated as errors \ 
(Commit: edbef4df, PR: #3809)
- Use void casts to silence warnings about memcpy to a class (Commit: 6746bc48, \ 
PR: #3800)