glgsg: Fix p3d_LightModel.ambient not updating properly

panda/src/glstuff/glShaderContext_src.cxx

@@ -1293,7 +1293,7 @@ reflect_uniform(int i, char *name_buffer, GLsizei name_buflen) {
       bind._func = Shader::SMF_first;
       bind._part[0] = Shader::SMO_light_ambient;
       bind._arg[0] = nullptr;
-      bind._dep[0] = Shader::SSD_general | Shader::SSD_light;
+      bind._dep[0] = Shader::SSD_general | Shader::SSD_light | Shader::SSD_frame;
       bind._part[1] = Shader::SMO_identity;
       bind._arg[1] = nullptr;
       bind._dep[1] = Shader::SSD_NONE;