- fixed sprite and particle colors when not affected by dynlights

When gl_light_sprites and/or gl_light_particles CVARs were unset, random values could be used their colors

https://forum.zdoom.org/viewtopic.php?t=67066

src/rendering/hwrenderer/scene/hw_sprites.cpp

@@ -146,7 +146,7 @@ void HWSprite::DrawSprite(HWDrawInfo *di, FRenderState &state, bool translucent)
 		{
 			if (dynlightindex == -1)	// only set if we got no light buffer index. This covers all cases where sprite lighting is used.
 			{
-				float out[3];
+				float out[3] = {};
 				di->GetDynSpriteLight(gl_light_sprites ? actor : nullptr, gl_light_particles ? particle : nullptr, out);
 				state.SetDynLight(out[0], out[1], out[2]);
 			}