Update FFmpeg to 7.1
Needs the usual branching cc @tpm.
Of specal note is amyspark/ffmpeg@8e2c68bd, which is needed for both stock and Meson build to work on MSVC (upstream didn't test gmtime_r).
Fixes #50
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Needs the usual branching cc @tpm.
Of specal note is amyspark/ffmpeg@8e2c68bd, which is needed for both stock and Meson build to work on MSVC (upstream didn't test gmtime_r).
Fixes #50