[qt_common, core, audio] remove duplicate string literal definitions, inline SystemManager::threadfunc, increase latency of audio shutdown (#3030)

Very small code cleanup, also remove `[[unlikely]]` because it doesn't matter + increase latency of audio render when shutting down

Signed-off-by: lizzie lizzie@eden-emu.dev

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/3030
Reviewed-by: Caio Oliveira <caiooliveirafarias0@gmail.com>
Reviewed-by: crueter <crueter@eden-emu.dev>
Co-authored-by: lizzie <lizzie@eden-emu.dev>
Co-committed-by: lizzie <lizzie@eden-emu.dev>

src/yuzu/bootmanager.cpp

@@ -71,8 +71,7 @@ EmuThread::EmuThread(Core::System& system) : m_system{system} {}
 EmuThread::~EmuThread() = default;
 
 void EmuThread::run() {
-    const char* name = "EmuControlThread";
-    Common::SetCurrentThreadName(name);
+    Common::SetCurrentThreadName("EmuControlThread");
 
     auto& gpu = m_system.GPU();
     auto stop_token = m_stop_source.get_token();