This formats all copyright comments according to SPDX formatting guidelines.
Additionally, this resolves the remaining GPLv2 only licensed files by relicensing them to GPLv2.0-or-later.
```
In file included from citra/src/audio_core/sink_details.cpp:11:
citra/src/./audio_core/sdl2_sink.h:25:10: warning: 'SetDevice' overrides a member function but is not marked 'override' [-Winconsistent-missing-override]
void SetDevice(int device_id);
^
citra/src/./audio_core/sink.h:39:18: note: overridden virtual function is here
virtual void SetDevice(int device_id) = 0;
^
```
* Initial Commit
Added Device logic to Sinks
Started on UI for selecting devices
Removed redundant import
* Audio Core: Complete Device Switching
Complete the device switching implementation by allowing the output
device to be loaded, changed and saved through the configurations menu.
Worked with the Sink abstraction and tuned the "Device Selection"
configuration so that the Device List is automatically populated when
the Sink is changed.
This hopefully addresses the concerns and recommendations mentioned in
the comments of the PR.
* Clean original implementation.
* Refactor GetSinkDetails