Avoid -Wshadow warning

Co-authored-by: Mai M. <mathew1800@gmail.com>

src/yuzu_cmd/emu_window/emu_window_sdl2_gl.cpp

@@ -32,7 +32,7 @@
 
 class SDLGLContext : public Core::Frontend::GraphicsContext {
 public:
-    explicit SDLGLContext(SDL_Window* window) : window(window) {
+    explicit SDLGLContext(SDL_Window* window_) : window{window_} {
         context = SDL_GL_CreateContext(window);
     }