Remove unused workaround code

Author: halx99

core/platform/android/Application-android.cpp

@@ -34,15 +34,6 @@ THE SOFTWARE.
 #define LOG_TAG "Application_android Debug"
 #define LOGD(...) __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG, __VA_ARGS__)
 
-// FIXME: using ndk-r10c will cause the next function could not be found. It may be a bug of ndk-r10c.
-// Here is the workaround method to fix the problem.
-#ifdef __aarch64__
-extern "C" size_t __ctype_get_mb_cur_max(void)
-{
-    return (size_t)sizeof(wchar_t);
-}
-#endif
-
 static const char* applicationHelperClassName = "dev.axmol.lib.AxmolEngine";
 
 namespace ax