Do not call vpn_progress() after forking

It's suboptimal that we only write to stderr, but calling the progress_fn
from a fork is going to cause all kinds of problems. Either we leave it
as it is or we come up with a saner way of passing the message back.

Perhaps a *new* 'child_write_progress' function which the caller can
provide, which does IPC or something. For now, stderr will suffice.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

tun.c

@@ -472,12 +472,12 @@ int openconnect_setup_tun_script(struct openconnect_info *vpninfo,
 		return -EIO;
 	} else if (!child) {
 		if (setpgid(0, getpid()) < 0)
-			vpn_perror(vpninfo, _("setpgid"));
+			perror(_("setpgid"));
 		close(fds[0]);
 		script_setenv_int(vpninfo, "VPNFD", fds[1]);
 		apply_script_env(vpninfo->script_env);
 		execl("/bin/sh", "/bin/sh", "-c", vpninfo->vpnc_script, NULL);
-		vpn_perror(vpninfo, _("execl"));
+		perror(_("execl"));
 		exit(1);
 	}
 	close(fds[1]);