swapon(8): adapt to the new swapoff(2) interface

also fix test sys/audit/administrative.c.

Reviewed by:	brooks
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D33343

sbin/swapon/swapon.c

@@ -789,18 +789,12 @@ swapon_trim(const char *name)
 static const char *
 swap_on_off_sfile(const char *name, int doingall)
 {
-	struct swapoff_new_args sa;
 	int error;
 
 	if (which_prog == SWAPON)
 		error = Eflag ? swapon_trim(name) : swapon(name);
-	else { /* SWAPOFF */
-		bzero(&sa, sizeof(sa));
-		sa.name = name;
-		if (fflag)
-			sa.flags |= SWAPOFF_FORCE;
-		error = swapoff((const char *)&sa);
-	}
+	else /* SWAPOFF */
+		error = swapoff(name, fflag ? SWAPOFF_FORCE : 0);
 
 	if (error == -1) {
 		switch (errno) {

tests/sys/audit/administrative.c

@@ -1605,7 +1605,7 @@ ATF_TC_BODY(swapoff_failure, tc)
 
 	FILE *pipefd = setup(fds, auclass);
 	/* Failure reason: Block device required */
-	ATF_REQUIRE_EQ(-1, swapoff(path));
+	ATF_REQUIRE_EQ(-1, swapoff(path, 0));
 	check_audit(fds, adregex, pipefd);
 }