[core, desktop] "fixes" from building on mxe/x86_64-w64-mingw32 (#396)

* well, i couldn't build the executable, but in anyway those build
  errors can come back later to bite our backs
* include missing include
* safeguard _MSC_VER only headers

* saw some of those changes on another PR but I cant find it at moment

Signed-off-by: Caio Oliveira <caiooliveirafarias0@gmail.com>

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/396
Reviewed-by: crueter <crueter@eden-emu.dev>
Co-authored-by: Caio Oliveira <caiooliveirafarias0@gmail.com>
Co-committed-by: Caio Oliveira <caiooliveirafarias0@gmail.com>

src/core/hle/service/nifm/nifm.cpp

@@ -21,6 +21,7 @@
 #include <atomic>
 #include <chrono>
 #include <mutex>
+#include <optional>
 #include <thread>
 #include <unordered_set>
 #include <common/settings.h>
@@ -32,8 +33,10 @@
 #undef interface
 #include <wlanapi.h>
 #pragma pop_macro("interface")
+#ifdef _MSC_VER
 #pragma comment(lib, "wlanapi.lib")
 #endif
+#endif
 
 namespace {