external: glfw: Revert "Added WinMM library"

This reverts commit 4773de26a50c29ae918e306c9936ad9d4ebf80aa.

which adds -lwinmm at the wrong place. It should be in the raylib
linker flags, not GLFW's.

src/external/glfw/CMakeLists.txt

@@ -190,7 +190,7 @@ endif()
 #--------------------------------------------------------------------
 if (_GLFW_WIN32)
 
-    list(APPEND glfw_PKG_LIBS "-lgdi32 -lwinmm")
+    list(APPEND glfw_PKG_LIBS "-lgdi32")
 
     if (GLFW_USE_HYBRID_HPG)
         set(_GLFW_USE_HYBRID_HPG 1)