Use <string.h> & <3ds/exheader.h>, fix some bugs, etc.

also fix all warnings and use -Werror

sysmodules/pxi/source/MyThread.c

@@ -7,7 +7,6 @@ This is part of 3ds_pxi, which is licensed under the MIT license (see LICENSE fo
 */
 
 #include "MyThread.h"
-#include "memory.h"
 
 static void _thread_begin(void* arg)
 {

sysmodules/pxi/source/main.c

@@ -6,12 +6,13 @@ main.c
 This is part of 3ds_pxi, which is licensed under the MIT license (see LICENSE for details).
 */
 
+#include <string.h>
+
 #include "PXI.h"
 #include "common.h"
 #include "MyThread.h"
 #include "receiver.h"
 #include "sender.h"
-#include "memory.h"
 
 Handle PXISyncInterrupt = 0, PXITransferMutex = 0;
 Handle terminationRequestedEvent = 0;

sysmodules/pxi/source/memory.c

@@ -1,19 +0,0 @@
-/*
-memory.c:
-    Memory functions
-
-(c) TuxSH, 2016-2017
-This is part of 3ds_pxi, which is licensed under the MIT license (see LICENSE for details).
-*/
-
-#include "memory.h"
-
-//Adpated from CakesFW
-void memcpy(void *dest, const void *src, u32 size)
-{
-    u8 *destc = (u8 *)dest;
-    const u8 *srcc = (const u8 *)src;
-
-    for(u32 i = 0; i < size; i++)
-        destc[i] = srcc[i];
-}

sysmodules/pxi/source/memory.h

@@ -1,13 +0,0 @@
-/*
-memory.h:
-    Memory functions
-
-(c) TuxSH, 2016-2017
-This is part of 3ds_pxi, which is licensed under the MIT license (see LICENSE for details).
-*/
-
-#pragma once
-
-#include <3ds/types.h>
-
-void memcpy(void *dest, const void *src, u32 size);

sysmodules/pxi/source/receiver.c

@@ -6,9 +6,10 @@ receiver.c:
 This is part of 3ds_pxi, which is licensed under the MIT license (see LICENSE for details).
 */
 
+#include <string.h>
+
 #include "receiver.h"
 #include "PXI.h"
-#include "memory.h"
 
 static inline void receiveFromArm9(void)
 {

sysmodules/pxi/source/sender.c

@@ -7,9 +7,10 @@ sender.c
 This is part of 3ds_pxi, which is licensed under the MIT license (see LICENSE for details).
 */
 
+#include <string.h>
+
 #include "sender.h"
 #include "PXI.h"
-#include "memory.h"
 
 Result sendPXICmdbuf(Handle *additionalHandle, u32 serviceId, u32 *buffer)
 {