yuzu/bootmanager: Explicitly enable deprecated OpenGL features on compat

yuzu/util: Remove unused spinbox.cpp/.h

This has been left unused since the removal of the vestigial surface
viewer. Given it has no uses left, this can be removed as well.

yuzu/{about_dialog, main}: Specify string conversions explicitly for SCM-related info

yuzu_cmd: Make OpenGL's context current

yuzu_cmd: Use OpenGL compat when asked in the settings

qt/configure_graphics: Shadow options at runtime

Compatibility profile and the disk shader cache settings shouldn't
be changed at runtime. This aims to address that shadowing those
options.

The SDL2 frontend never bound the OpenGL context, resulting on a white
screen and no-ops all over the backend.

Nvidia's proprietary driver creates a real OpenGL compatibility profile
without this option, meanwhile Intel (and probably AMD, I haven't tested
it) require that QSurfaceFormat::FormatOption::DeprecatedFunctions is
explicitly enabled.

video_core/memory_manager: Minor tidying

video_core: Remove a few unused variables and functions

CMakeLists: Specify /volatile:iso for MSVC

CMakeLists: Explicitly specify -Wall for the non-MSVC case

Rasterizer Cache: refactor flushing & optimize memory usage of surfaces

Corrects the typo in its name and marks the function as a const member
function, given it doesn't actually modify memory manager state.

Prevents implicit converting constructions of the memory manager.

Makes the class less surprising when it comes to forward declaring the
type, and also prevents inlining the destruction code of the class,
given it contains non-trivial types.

Corrects references to non-existent parameters and corrects typos.

These are able to be omitted from the declaration of functions, since
they don't do anything at the type system level. The definitions of the
functions can retain the use of const though, since they make the
variables immutable in the implementation of the function where they're
used.

Silences a -Wreorder warning.

This isn't used at all, so it can be removed.

This variable is unused entirely, so it can be removed.

Instead of retrieving the data from the std::variant instance, we can
just check if the variant contains that type of data.

This is essentially the same behavior, only it returns a bool indicating
whether or not the type in the variant is currently active, instead of
actually retrieving the data.

Silences a few compilation warnings.

By default, MSVC doesn't use standards-compliant volatile semantics.
This makes it behave in a standards-compliant manner, making
expectations more uniform across compilers.

service/audctl: Update documentation comments to be relative to 8.0.0

src/CMakeLists: Add /Zc:externConstexpr to the MSVC build flags

Fix Layered ASTC Textures

gl_shader_disk_cache: Skip stored shader variants instead of asserting

Port citra-emu/citra#4749: "web_service: Misc fixes"

yuzu/hotkeys: Remove unnecessary constructor

yuzu/compatdb: Remove unnecessary qualifiers

configure_dialog: Remove the Whats This? button from the dialog

core/memory: Remove unused FlushMode enum

Corrections and Implementation on GPU Engines

externals: Update dynarmic to master