audren_u: Use a std::array instead of std::string for holding the audio interface/device name

std::string doesn't include the null-terminator in its data() + size()
range. This ensures that the null-terminator will also be written to the buffer

src/core/hle/service/audio/audren_u.cpp

@@ -2,6 +2,8 @@
 // Licensed under GPLv2 or any later version
 // Refer to the license.txt file included.
 
+#include <array>
+
 #include "common/alignment.h"
 #include "common/logging/log.h"
 #include "core/core_timing.h"
@@ -298,7 +300,7 @@ private:
         LOG_WARNING(Service_Audio, "(STUBBED) called");
         IPC::RequestParser rp{ctx};
 
-        const std::string audio_interface = "AudioInterface";
+        constexpr std::array<char, 15> audio_interface{{"AudioInterface"}};
         ctx.WriteBuffer(audio_interface);
 
         IPC::ResponseBuilder rb = rp.MakeBuilder(3, 0, 0);
@@ -323,7 +325,7 @@ private:
         LOG_WARNING(Service_Audio, "(STUBBED) called");
         IPC::RequestParser rp{ctx};
 
-        const std::string audio_interface = "AudioDevice";
+        constexpr std::array<char, 12> audio_interface{{"AudioDevice"}};
         ctx.WriteBuffer(audio_interface);
 
         IPC::ResponseBuilder rb = rp.MakeBuilder(3, 0, 0);