vulkan: document future possibility for vsync

Right now we have to recreate the swapchain everytime vsync
/ present mode changes.
VK_EXT_swapchain_maintenance1 might remove the need for this.
However, right now there are not any drivers yet that support it.
In the future, this might be the better way to handle this situation.

src/modules/graphics/vulkan/Graphics.cpp

@@ -2702,6 +2702,11 @@ void Graphics::setVsync(int vsync)
 	{
 		this->vsync = vsync;
 
+		// With the extension VK_EXT_swapchain_maintenance1 a swapchain recreation might not be needed
+		// https://github.com/KhronosGroup/Vulkan-Docs/blob/main/proposals/VK_EXT_swapchain_maintenance1.adoc
+		// However, there are not any drivers that support it, yet.
+		// Reevaluate again in the future.
+
 		requestSwapchainRecreation();
 	}
 }