Update libmlt to version 7.8.0 / rev 62 via SR 993436
https://build.opensuse.org/request/show/993436
by user plater + dimstar_suse
- Add upstream changes to build a Qt 6 based mod:
* 0001-Split-to-allow-installing-Qt5-and-Qt6-in-parallel-80.patch
* 0002-Remove-deprecated-C-register-keyword-815.patch
* 0003-Move-CMake-code-for-testing-to-the-right-position-fo.patch
* 0004-Add-MLT_REPOSITORY_DENY-envvar-to-skip-plugin-loadin.patch
* 0005-Avoid-to-load-both-qt-modules-816.patch