Adds the following actions:
- Remove Installed Update
- Remove All Installed DLC
- Remove Shader Cache
- Remove Custom Configuration
- Remove All Installed Contents

device_memory: Remove unused system member

configure_graphics: Remove Force 30 FPS mode

The introduction of multicore rendered this setting non-functional as timing code was changed.

This removes the setting entirely.

This isn't used by anything in particular, so it can be removed.

core_timing: Make use of uintptr_t to represent user_data

qt_themes: Set QLabel background color to transparent for Dark and Midnight Blue themes

Makes the interface future-proofed for supporting other platforms in the event we ever support platforms with differing pointer sizes. This way, we have a type in place that is always guaranteed to be able to represent a pointer exactly.

vulkan: Resolve -Wmissing-field-initializer warnings

AM: GetDesiredLanguage: remove unused variable

video_core/gpu: Correct the size of the puller registers

GCAdapter: only join worker thread if running & joinable

The puller register array is made up of u32s however the `NUM_REGS` value is the size in bytes, so switch it to avoid making the struct unnecessary large. Also fix a small typo in a comment.

nvflinger: Use return value of Lock()

udp/client: Remove unused boost include

virtual_buffer: Mark size parameter of FreeMemoryPages() as [[maybe_unused]]

gc_adapter/gc_poller: Resolve compiler warnings

yuzu/configure_debug: Remove duplicated checkboxes

Those are already found in the Filesystem tab.
They were added back to the Debug tab by mistake in the Vulkan PR.

Not using the return value of these functions are undeniably the source
of a bug. This way we allow compilers to loudly make any future misuses
evident.

comex reported in #4424 that we were incorrectly discarding the return
value of Lock() which is correct.

hid: Only update keyboard & debug pad inputs if enabled

This function was relocated to log.h as a constexpr function, so this
can be removed.

Fixes the override highlights in per-game settings from looking weird when viewed on the Dark or Midnight Blue themes by setting QLabels to have transparent backgrounds by default.

Also apparently adds a newline to the end of the Dark theme's qss file.

Also silences a deprecation warning from boost on Clang/GCC.

This isn't used on Windows, but is used on non-Windows operating
systems.

swkbd: Return result for Calc request for inlined swkbd

frontend: Match indeterminate checkbox state with light theme

vk_rasterizer: Remove unused variable in Clear()

qt-themes: Add Midnight Blue qdarkstyle theme (2.8.1)

configure_per_game: Clearer per-game settings

buffer_cache: Eliminate redundant map lookup in MarkRegionAsWritten()

video_core: Allow copy elision to take place where applicable

video_core: Remove unused variables