Add explicit cast (gl_InstanceID is int), fixes errors on mesa compiler
Add explicit cast (gl_InstanceID is int), fixes errors on mesa compiler

Lssikkes/renderdoc,baldurk/renderdoc,victor-moya/renderdoc,Anteru/renderdoc,cgmb/renderdoc,Zorro666/renderdoc,Velro/renderdoc,TurtleRockStudios/renderdoc_public,etnlGD/renderdoc,cgmb/renderdoc,Velro/renderdoc,etnlGD/renderdoc,Zorro666/renderdoc,Yours3lf/renderdoc,Velro/renderdoc,TurtleRockStudios/renderdoc_public,victor-moya/renderdoc,Zorro666/renderdoc,cgmb/renderdoc,michaelrgb/renderdoc,Zorro666/renderdoc,Velro/renderdoc,Yours3lf/renderdoc,michaelrgb/renderdoc,Anteru/renderdoc,etnlGD/renderdoc,victor-moya/renderdoc,michaelrgb/renderdoc,Lssikkes/renderdoc,TurtleRockStudios/renderdoc_public,Zorro666/renderdoc,googlestadia/renderdoc,Anteru/renderdoc,Anteru/renderdoc,Velro/renderdoc,cgmb/renderdoc,Yours3lf/renderdoc,Anteru/renderdoc,googlestadia/renderdoc,googlestadia/renderdoc,Anteru/renderdoc,googlestadia/renderdoc,TurtleRockStudios/renderdoc_public,etnlGD/renderdoc,googlestadia/renderdoc,baldurk/renderdoc,Yours3lf/renderdoc,Anteru/renderdoc,baldurk/renderdoc,baldurk/renderdoc,victor-moya/renderdoc,etnlGD/renderdoc,Lssikkes/renderdoc,TurtleRockStudios/renderdoc_public,Yours3lf/renderdoc,michaelrgb/renderdoc,Zorro666/renderdoc,baldurk/renderdoc,Lssikkes/renderdoc,baldurk/renderdoc,victor-moya/renderdoc,TurtleRockStudios/renderdoc_public,Yours3lf/renderdoc,cgmb/renderdoc,victor-moya/renderdoc,Lssikkes/renderdoc,michaelrgb/renderdoc,Lssikkes/renderdoc,Velro/renderdoc,etnlGD/renderdoc,googlestadia/renderdoc