dhclient(8) should not close stdio using daemon(3) function.

dhclient(8) is chrooted so opening /dev/null always will fail.
In capability world this is also annoying because we getting error that
open(2) is not permitted in Capsicum. dhclient(8) is closing stdio by
precaching fd to /dev/null before chroot.
This is done few lines below daemon(3) function so let's not try to do that
in daemon(3) function.

Reviewed by:	cem@
Differential Revision:	https://reviews.freebsd.org/D12826

sbin/dhclient/dhclient.c

@@ -2423,7 +2423,7 @@ go_daemon(void)
 	/* Stop logging to stderr... */
 	log_perror = 0;
 
-	if (daemon(1, 0) == -1)
+	if (daemon(1, 1) == -1)
 		error("daemon");
 
 	cap_rights_init(&rights);