Silence warning.
 [rsc] --rw-rw-r-- M 1146153 rsc sys 5247 Dec 30 11:01 sys/src/cmd/tcs/html.c
	/n/sourcesdump/2005/1230/plan9/sys/src/cmd/tcs/html.c:314,319 - 
	/n/sourcesdump/2005/1231/plan9/sys/src/cmd/tcs/html.c:314,320
	  	Biobuf b;
	  	Rune *er;
	  	
	+ 	USED(x);
	  	html_init();
	  	Binit(&b, 1, OWRITE);
	  	er = r+n;