Make yubikey less picky about what it'll generate tokens for

The protocol should validate which form fields are OK; no need to apply
CSTP-specific filters (which are now out of date) in the yubikey code.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>

yubikey.c

@@ -480,8 +480,7 @@ int can_gen_yubikey_code(struct openconnect_info *vpninfo,
 			 struct oc_auth_form *form,
 			 struct oc_form_opt *opt)
 {
-	if ((strcmp(opt->name, "secondary_password") != 0) ||
-	    vpninfo->token_bypassed)
+	if (vpninfo->token_bypassed)
 		return -EINVAL;
 	if (vpninfo->token_tries == 0) {
 		vpn_progress(vpninfo, PRG_DEBUG,