Bug 5094 - Code cleanup, patch by Zack Middleton and DevHC. Fixes unused-but-set gcc warnings

code/renderer/tr_backend.c

@@ -753,7 +753,7 @@ void RE_StretchRaw (int x, int y, int w, int h, int cols, int rows, const byte *
 	// we definately want to sync every frame for the cinematics
 	qglFinish();
 
-	start = end = 0;
+	start = 0;
 	if ( r_speeds->integer ) {
 		start = ri.Milliseconds();
 	}