Fix overly dim Light3D nodes when using directional lightmap baking

Author: Rudolph-B

modules/lightmapper_rd/lm_compute.glsl

@@ -467,7 +467,9 @@ void trace_direct_light(vec3 p_position, vec3 p_normal, uint p_light_index, bool
 		}
 	}
 
+#ifndef USE_SH_LIGHTMAPS
 	attenuation *= max(0.0, dot(p_normal, r_light_dir));
+#endif
 	if (attenuation <= 0.0001) {
 		return;
 	}