common/file_util: Address review comments of #5174

travis/linux: Use correct ccache directory

nim: Stub IsLargeResourceAvailable

Changes the bound ccache directory to `/home/yuzu/.ccache` instead of
`/root/.ccache`, since the `/root` directory is not accessible by the
`yuzu` user in the guest container.

gl_shader_decompiler: Elide unnecessary copies within DeclareConstantBuffers()

common/file_util: Let std::filesystem cast from UTF16 to std::string

Fix invalid encoding paths when iterating over a directory on Windows.

vfs_real: Fix CreateFile for files without a file extension

common/file_util: Fix and deprecate CreateFullPath, add CreateDirs

Fix CreateFullPath to have its intended previous behavior (whatever
that was), and deprecate it in favor of the new CreateDirs function.

Unlike CreateDir, CreateDirs is marked as [[nodiscard]] to avoid new
code ignoring its result value.

network, sockets: Replace `POLL_IN`, `POLL_OUT`, etc. constants with an `enum class PollEvents`

common/file_util: Make use of std::filesystem

Converts creation and deletion functions over to std::filesystem,
simplifying our file-handling code.

Notably with this, CopyDir will now function on Windows.

core: Remove unnecessary enum casts in log calls

applets: Resolve variable shadowing

Greatly simplifies our file-handling code for these functions.

ci: Remove `-DYUZU_USE_BUNDLED_UNICORN=ON`

Unicorn has been removed, yet CI still enables building with Unicorn.
This just cleans up a few leftovers by removing the variable from the
CMake parameters in CI.

memory: Resolve -Wdocumentation warning for Write()

Write() doesn't return anything, so the @returns tag shouldn't be
present.

configure_motion_touch: Fix unescaped backslash in regex

controller: Avoid unnecessary copies in ConfigurationComplete()

Follows the video core PR. fmt doesn't require casts for enum classes
anymore, so we can remove quite a few casts.

Avoids unnecessary copies.

Avoids unnecessary 1072 byte copies when querying info about
controllers.

Disable analog joystick from buttons by default

video_core: Make use of ordered container contains() where applicable

ast: Improve string concat readability in operator()

CMakeLists,network: Create YUZU_UNIX macro to replace __unix__

With C++20, we can use the more concise contains() member function
instead of comparing the result of the find() call with the end
iterator.

Provides an in-place format string to make it more pleasant to read.

Resolves a -Wrange-loop-analysis warning.

map_interval: Change field order to address uninitialized field warning

shader_ir: std::move node within DeclareAmend()

buffer_block: Remove unnecessary includes

Prevents logic errors from occurring from unused values.