grep: fix combination of quiet and count flag

When the quiet (-q) flag is provided, we don't expect any output.
Currently, the behavior is broken:
$ grep -cq flag util.c
1

$ grep -cs flag util.c
55

First of all, we print a number to stdout. Secondly, it just returns
0 or 1 (which is unexpected). GNU grep with c and q flags doesn't
print anything.

Reviewed by:	markj
Differential Revision:	https://reviews.freebsd.org/D31108

(cherry picked from commit 24c681a7f6)

usr.bin/grep/util.c

@@ -388,7 +388,7 @@ procfile(const char *fn)
 		clearqueue();
 	grep_close(f);
 
-	if (cflag) {
+	if (cflag && !qflag) {
 		if (!hflag)
 			printf("%s:", pc.ln.file);
 		printf("%u\n", lines);