game_list: Join declarations and assignments in onTextChanged()

qt/main: Collapse if statement in UpdateRecentFiles()

qt: Don't show error dialog when canceling the Load Folder dialog

qt: Minor cleanup-related changes

kernel/event: Make data members private

gl_rasterizer_cache: Avoid superfluous surface copies.

 core_timing: Make GetGlobalTimeUs() return std::chrono::microseconds

qt/main: Better file-existence checking within OnMenuRecentFile() and UpdateUITheme()

This was intermixing signed and unsigned values when they could all just
be signed.

There's no need to keep these separate from one another.

Given the function accepts a boolean, we don't need to use an if
statement here and repeat ourselves.

In OnMenuRecentFile() we don't need to construct a QFileInfo instance
just to check if a file exists, we can just use the static member
function to do that (which Qt's documentation also notes as quicker than
constructing an instance).

In UpdateUITheme(), we just want to try and open the file and check the
success of that operation. Technically speaking, between the existence
check and the open call, the file can be deleted or moved, but still
appear to succeed in code. i.e.

1. Existence check -> Returns true
2. File is moved/deleted
3. Open is called, the return value of which isn't checked
4. Nonsense behavior

This way we combine the existence check and the open into one.

Previously, when canceling out of the Load Folder dialog, a user would
get an error dialog about the selected folder not containing a main
file, however, by canceling out of the dialog, no selection was actually
made.

These occur automatically without the need to call them. While we're at
it, also std::move the QString instance into its member variable.

Makes code consistent with our style of defaulting special member
functions where applicable.

Instead we can simply provide accessors to the required data instead of
giving external read/write access to the variables directly.

memory: Correct prototype of ZeroBlock

Service/Audio: audout_a.cpp: remove pragma once

core_timing: Use transparent functors where applicable

gdbstub: Minor changes

address_arbiter: Return by value from GetThreadsWaitingOnAddress()

Implement audren audio output

ms is shorthand for milliseconds, not microseconds, and given there's no
comment indicating that this was intentional, it probably wasn't.

Enforces the time unit being returned and also allows using the standard
time utilities to manipulate it.

Keeps the code consistent.

Previously, the prototype wasn't matching the definition, which has a
Processor parameter before the destination address.

These aren't necessary, as value-wise const only matters in the
definition.

Makes the alias a little more readable from left-to-right.

Gets rid of the need to hardcode the type in multiple places. This will
now be deduced automatically, based off the elements in the container
being provided to the algorithm.

gl_shader_decompiler: Fix TEXS mask and dest.

Rather than having to type out the full std::map type signature, we can
just use a straightforward alias. While we're at it, rename
GetBreakpointList to GetBreakpointMap, which makes the name more
accurate. We can also get rid of unnecessary u64 static_casts, since
VAddr is an alias for a u64.

Keeps everything under the same namespace. While we're at it, enclose
them all within an inner anonymous namespace.

video_core: Eliminate the g_renderer global variable

In all cases the vector being supplied is empty, so we can just return
by value in these instances.

In all cases, a virtual address is being passed in, not a physical one.

externals: Update dynarmic to 4f96c63