del ikpmp3 files

premake/ikpmp3/ikpMP3.h

-#include <irrKlang.h>
-
-namespace irrklang
-{
-#ifdef WIN32
-	// Windows version
-	extern "C" __declspec(dllexport) void ikpMP3Init(ISoundEngine* engine);
-#else
-	// Linux version
-	extern "C" void ikpMP3Init(ISoundEngine* engine);
-#endif
-}
\ No newline at end of file

premake/ikpmp3/ikpmp3.patch

-diff -ur ikpmp3/CIrrKlangAudioStreamMP3.cpp ikpmp3-static/CIrrKlangAudioStreamMP3.cpp
---- ikpmp3/CIrrKlangAudioStreamMP3.cpp	2009-01-02 07:33:40.000000000 +0800
-+++ ikpmp3-static/CIrrKlangAudioStreamMP3.cpp	2017-11-27 19:18:34.295546800 +0800
-@@ -8,6 +8,7 @@
- #include <memory.h>
- #include <stdlib.h> // free, malloc and realloc
- #include <string.h>
-+#include <algorithm>
- 
- namespace irrklang
- {
-diff -ur ikpmp3/ikpMP3.cpp ikpmp3-static/ikpMP3.cpp
---- ikpmp3/ikpMP3.cpp	2007-10-28 18:14:00.000000000 +0800
-+++ ikpmp3-static/ikpMP3.cpp	2017-11-27 19:49:02.119092400 +0800
-@@ -6,30 +6,14 @@
- 
- using namespace irrklang;
- 
--// this is the only function needed to be implemented for the plugin, it gets
--// called by irrKlang when loaded.
--// In this plugin, we create an audiostream loader class and register
--// it at the engine, but a plugin can do anything.
--// Be sure to name the function 'irrKlangPluginInit' and let the dll start with 'ikp'.
--
- #ifdef WIN32
- // Windows version
--__declspec(dllexport) void __stdcall irrKlangPluginInit(ISoundEngine* engine, const char* version)
-+extern "C" __declspec(dllexport) void ikpMP3Init(ISoundEngine* engine)
- #else
- // Linux version
--void irrKlangPluginInit(ISoundEngine* engine, const char* version)
-+extern "C" void ikpMP3Init(ISoundEngine* engine)
- #endif
- {
--	// do some version security check to be sure that this plugin isn't begin used
--	// by some newer irrKlang version with changed interfaces which could possibily
--	// cause crashes.
--
--	if (strcmp(version, IRR_KLANG_VERSION))
--	{
--		printf("This MP3 plugin only supports irrKlang version %s, mp3 playback disabled.\n", IRR_KLANG_VERSION);
--		return;
--	}
--
- 	// create and register the loader
- 
- 	CIrrKlangAudioStreamLoaderMP3* loader = new CIrrKlangAudioStreamLoaderMP3();

premake/ikpmp3/premake4.lua

-project "ikpmp3"
-    kind "StaticLib"
-
-    files { "*.cpp", "*.h", "decoder/*.c", "decoder/*.h" }
-	includedirs { "../irrklang/include" }