audio: Add files to CMake.

src/core/CMakeLists.txt

@@ -41,6 +41,8 @@ set(SRCS
             hle/service/am/applet_oe.cpp
             hle/service/aoc/aoc_u.cpp
             hle/service/apm/apm.cpp
+            hle/service/audio/audio.cpp
+            hle/service/audio/audout_u.cpp
             hle/service/hid/hid.cpp
             hle/service/lm/lm.cpp
             hle/service/nvdrv/devices/nvdisp_disp0.cpp
@@ -124,6 +126,8 @@ set(HEADERS
             hle/service/am/applet_oe.h
             hle/service/aoc/aoc_u.h
             hle/service/apm/apm.h
+            hle/service/audio/audio.h
+            hle/service/audio/audout_u.h
             hle/service/hid/hid.h
             hle/service/lm/lm.h
             hle/service/nvdrv/devices/nvdevice.h

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

@@ -2,7 +2,6 @@
 // Licensed under GPLv2 or any later version
 // Refer to the license.txt file included.
 
-#include "core/hle/ipc_helpers.h"
 #include "core/hle/service/audio/audio.h"
 #include "core/hle/service/audio/audout_u.h"