Set global definition WIN32_LEAN_AND_MEAN (#2807)

Set definition WIN32_LEAN_AND_MEAN to avoid windows.h including a lot of libs that are usually not used.

CMakeLists.txt

@@ -79,6 +79,8 @@ else()
     add_definitions(/D_CRT_SECURE_NO_WARNINGS /D_CRT_NONSTDC_NO_DEPRECATE /D_SCL_SECURE_NO_WARNINGS)
     # Avoid windows.h junk
     add_definitions(/DNOMINMAX)
+    # Avoid windows.h from including some usually unused libs like winsocks.h, since this might cause some redefinition errors.
+    add_definitions(/DWIN32_LEAN_AND_MEAN)
 
     # set up output paths for executable binaries (.exe-files, and .dll-files on DLL-capable platforms)
     set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin)

src/citra/citra.cpp

@@ -18,7 +18,10 @@
 #endif
 
 #ifdef _WIN32
+// windows.h needs to be included before shellapi.h
 #include <windows.h>
+
+#include <shellapi.h>
 #endif
 
 #include "citra/config.h"