CMakeLists: Ensure we specify Unicode as the codepage on Windows

Previously we were building with MBCS, which is pretty undesirable. We
want the application to be Unicode-aware in general.

Currently, we make the command line variant of yuzu use ANSI variants of
the non-standard getopt functions that we link in for Windows, given we
only have an ANSI option-set.

We should really replace getopt with a library that we make all build
types of yuzu link in, but this will have to do for the time being.

src/citra/citra.cpp

@@ -11,11 +11,6 @@
 // This needs to be included before getopt.h because the latter #defines symbols used by it
 #include "common/microprofile.h"
 
-#include <getopt.h>
-#ifndef _MSC_VER
-#include <unistd.h>
-#endif
-
 #ifdef _WIN32
 // windows.h needs to be included before shellapi.h
 #include <windows.h>
@@ -45,6 +40,12 @@
 #include "core/settings.h"
 #include "network/network.h"
 
+#undef _UNICODE
+#include <getopt.h>
+#ifndef _MSC_VER
+#include <unistd.h>
+#endif
+
 #ifdef _WIN32
 extern "C" {
 // tells Nvidia drivers to use the dedicated GPU by default on laptops with switchable graphics