Correct a few OpenGL variable types

Affectly no change for desktop OpenGL.
Use correct types for OpenGLES support.

code/renderergl1/tr_backend.c

@@ -474,7 +474,7 @@ void RB_BeginDrawingView (void) {
 	// clip to the plane of the portal
 	if ( backEnd.viewParms.isPortal ) {
 		float	plane[4];
-		double	plane2[4];
+		GLdouble	plane2[4];
 
 		plane[0] = backEnd.viewParms.portalPlane.normal[0];
 		plane[1] = backEnd.viewParms.portalPlane.normal[1];