ref: soft: remove unused isSkyVisible

ref/soft/r_local.h

@@ -125,7 +125,6 @@ typedef struct
 	const ref_viewpass_t rvp;
 
 	qboolean    drawWorld;                  // ignore world for drawing PlayerModel
-	qboolean    isSkyVisible;               // sky is visible
 	qboolean    onlyClientDraw;             // disabled by client request
 	qboolean    drawOrtho;                  // draw world as orthogonal projection
 

ref/soft/r_main.c

@@ -502,10 +502,7 @@ static void R_SetupFrame( void )
 
 	// current viewleaf
 	if( RI.drawWorld )
-	{
-		RI.isSkyVisible = false; // unknown at this moment
 		R_FindViewLeaf();
-	}
 
 	// setup twice until globals fully refactored
 	R_SetupFrameQ();