CMake: Disable warnings and only build static lib for SDL from extern…

…als.

CMakeLists.txt

@@ -619,11 +619,22 @@ if(ENABLE_SDL)
     message(STATUS "Using system SDL2")
   else()
     message(STATUS "Using static SDL2 from Externals")
+    set(SDL2_DISABLE_SDL2MAIN OFF)
+    set(SDL2_DISABLE_INSTALL OFF)
+    set(SDL2_DISABLE_UNINSTALL OFF)
     set(SDL_SHARED OFF)
     set(SDL_SHARED_ENABLED_BY_DEFAULT OFF)
     set(SDL_STATIC ON)
     set(SDL_STATIC_ENABLED_BY_DEFAULT ON)
+    set(SDL_TEST OFF)
+    set(SDL_TEST_ENABLED_BY_DEFAULT OFF)
     add_subdirectory(Externals/SDL/SDL)
+    if (TARGET SDL2)
+      dolphin_disable_warnings_msvc(SDL2)
+    endif()
+    if (TARGET SDL2-static)
+      dolphin_disable_warnings_msvc(SDL2-static)
+    endif()
     set(SDL2_FOUND TRUE)
   endif()
   add_definitions(-DHAVE_SDL2=1)