service: Remove redundant #pragma once directives

These don't do anything within .cpp files (we don't include cpp files,
so...)

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

@@ -2,8 +2,6 @@
 // Licensed under GPLv2 or any later version
 // Refer to the license.txt file included.
 
-#pragma once
-
 #include "core/hle/service/audio/audin_a.h"
 
 namespace Service::Audio {

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

@@ -2,8 +2,6 @@
 // Licensed under GPLv2 or any later version
 // Refer to the license.txt file included.
 
-#pragma once
-
 #include "core/hle/service/audio/audrec_a.h"
 
 namespace Service::Audio {

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

@@ -2,8 +2,6 @@
 // Licensed under GPLv2 or any later version
 // Refer to the license.txt file included.
 
-#pragma once
-
 #include "core/hle/service/audio/audren_a.h"
 
 namespace Service::Audio {

src/core/hle/service/filesystem/fsp_ldr.cpp

@@ -2,8 +2,6 @@
 // Licensed under GPLv2 or any later version
 // Refer to the license.txt file included.
 
-#pragma once
-
 #include "core/hle/service/filesystem/fsp_ldr.h"
 #include "core/hle/service/service.h"
 

src/core/hle/service/filesystem/fsp_pr.cpp

@@ -2,8 +2,6 @@
 // Licensed under GPLv2 or any later version
 // Refer to the license.txt file included.
 
-#pragma once
-
 #include "core/hle/service/filesystem/fsp_pr.h"
 #include "core/hle/service/service.h"