wcc: delete unused warning counters and ww err twin

cmd/wcc/parse.c

@@ -210,9 +210,8 @@ parsetype(Parser *p)
 		if (p->cur.kind == TK_AT) {
 			advance(p);
 			const char *an = expectident(p);
-			/* p->errs gates the build (cmd/w6c/main.c:82);
-			 * nerrors is advisory-only, so an errorf on a
-			 * clean-recovery path must bump p->errs itself. */
+			/* errorf only reports; p->errs gates the build
+			 * (cmd/w6c/main.c:82). */
 			if (strcmp(an, "packed") != 0) {
 				errorf(p->cur.pos,
 				    "unknown struct attribute '@%s'", an);