WIP

textures: Add a toggle for GPU Accelerated ASTC decoder 

fsp_srv: Fix filesystem access logging

The Append open mode will create a new file if said file does not exist at a given path, making this call redundant.

This introduces a new setting Enable FS Access Log which saves the filesystem access log to sdmc:/FsAccessLog.txt

If this setting is not enabled, this will indicate to FS to not call OutputAccessLogToSdCard.

Fixes softlocks during loading in Xenoblade Chronicles 2 when certain DLC is enabled.

common: fs: file: Flush the file to the disk when Flush() is called

Per the spec, L1 is clamped to the value 0xff if it is greater than 0xff. An oversight caused us to take the maximum of L1 and 0xff, rather than the minimum.

Huge thanks to wwylele for finding this.

Co-Authored-By: Weiyi Wang <wwylele@gmail.com>

Users may want to fall back to the CPU ASTC texture decoder due to hangs
and crashes that may be caused by keeping the GPU under compute heavy
loads for extended periods of time. This is especially the case in games
such as Astral Chain which make extensive use of ASTC textures.

lm: Demote LM guest logs to LOG_DEBUG

Guest logs are not very useful, as they are intended for use by the game developers during development. As such, they provide little meaning to be logged by yuzu and tend to overwhelm the log output at times.

configure_cpu_debug: Clarify settings behavior

common: fs: Use the normal directory iterator in *Recursively functions

common: logging: Restructure logging backend

Allows us to forward declare Common::FS::IOFile.

std::fflush does not guarantee that file buffers are flushed to the disk.

Use _commit on Windows and fsync on all other OSes to ensure that the file is flushed to the disk.

hid: Stub IsFirmwareUpdateAvailableForSixAxisSensor

This makes it clear that the disabled settings only take effect when CPU Accuracy is set to Debug Mode.

MSVC's implementation of recursive_directory_iterator throws an exception on an error despite a std::error_code being passed into its constructor. This is most likely a bug in MSVC's implementation since directory_iterator does not throw an exception on an error.

We can replace the usage of recursive_directory_iterator for now until MSVC fixes their implementation of it.

externals: Don't set FOUND or VERSION on LIBUSB

Fixes an issue where libusb.h wouldn't be found when building yuzu on
MSVC.

This only affects the "traditional" CMake pathway for linking libusb to
yuzu AKA MSVC. For autotools we still want to set these variables before
configuring SDL.

yuzu: main: Ensure enough space is available for RomFS dumping

Implement/Port Fastmem from Citra to Yuzu

This warns the user if there isn't enough free space to dump the entire RomFS to disk. It requires at least the size of the extracted RomFS + 1 GiB as a buffer of free space.

kernel: KLightConditionVariable: Update implementation to 12.x

This falls back to the old approach of using a virtual buffer.

Windows is untested, but this build should fix support for Windows < 10 v1803. However without fastmem support at all.

Workaround old headers and libraries shipped on MinGW.

In theory, if we have 2 MB continously mapped, this should save one layer of TLB.
Let's make it at least more likely by aligning the memory.