Fix GCC "declaration of ... changes meaning" errors.

PiperOrigin-RevId: 470175500
Change-Id: If13a81f308f803d3cc4731b3d4d0561cfe56d5c8

simulate/glfw_dispatch.cc

@@ -60,7 +60,7 @@ const struct Glfw& Glfw(void* dlhandle) {
       glfw.func = reinterpret_cast<decltype(glfw.func)>(dlsym(dlhandle, #func))
   #endif
 #else
-  #define mjGLFW_RESOLVE_SYMBOL(func) glfw.func = &func
+  #define mjGLFW_RESOLVE_SYMBOL(func) glfw.func = &::func
 #endif
 
 #define mjGLFW_INITIALIZE_SYMBOL(func)                  \

simulate/glfw_dispatch.h

@@ -22,7 +22,7 @@ namespace mujoco {
 // This allows us to use GLFW without introducing a link-time dependency on the
 // library, which is useful e.g. when using GLFW via Python.
 struct Glfw {
-#define mjGLFW_DECLARE_SYMBOL(func) decltype(&func) func
+#define mjGLFW_DECLARE_SYMBOL(func) decltype(&::func) func
   // go/keep-sorted start
   mjGLFW_DECLARE_SYMBOL(glfwCreateWindow);
   mjGLFW_DECLARE_SYMBOL(glfwGetCursorPos);