- This is closer to pre-multicore behavior, and works a bit better.

- This breaks things, and is unnecessary, since emulation will be done at this point.

Migrates the video core code closer to enabling variable shadowing
warnings as errors.

This primarily sorts out shadowing occurrences within the Vulkan code.

Co-Authored-By: xperia64 <xperia64@users.noreply.github.com>

This was only necessary for use with the
avcodec_decode_video2/avcoded_decode_audio4 APIs which are also
deprecated.

Given we use avcodec_send_packet/avcodec_receive_frame, this isn't
necessary, this is even indicated directly within the FFmpeg API changes
document here on 2017-09-26:

https://github.com/FFmpeg/FFmpeg/blob/master/doc/APIchanges#L410

This prevents our code from breaking whenever we update to a newer
version of FFmpeg in the future if they ever decide to fully remove this
API member.

Resolves variable shadowing scenarios up to the end of the OpenGL code
to make it nicer to review. The rest will be resolved in a following
commit.

Prevents logic bugs from accidentally ignoring the return value.

Removes the usage of moves that don't result in behavior different from
a copy, or otherwise would prevent copy elision from occurring.

Allows the struct to be constructed in place.

Removes the use of two static casts and improves the readability of some
vectors slightly.

Moves the audio code closer to enabling warnings as errors in general.

yuzu's web applet does not or barely reacts to user input while open in
Linux. It can be closed via 'Exit Web Applet' on the menubar, however if
yuzu is in fullscreen, this is effectively a softlock as the menubar
cannot be accessed.

This disables building yuzu with the web applet on the Linux CI target.
In addition, this disables the QMessageBox warning about not having
compiled yuzu with the web applet.

- This will be aligned by default, and helps memory usage.

It's unused and doesn't need to be initialized

This Clang warning complains when offsetof is used on a
non-standard-layout type (i.e. any class using various C++ features),
even though it works fine (and is not undefined behavior as of C++17).