HS 2.0: Fix sp_type check in ctrl_iface status command

Commit e99b4f3a14755473d6d0e2413de6d82e785a6a30 added functionality to
check whether the current association is with the home SP. This commit
did not take into account that the domain name ANQP information could be
NULL and that could result to a NULL pointer dereference. Fix that by
validation that domain_names != NULL before calling
domain_name_list_contains().

Signed-hostap: Jouni Malinen <jouni@qca.qualcomm.com>

wpa_supplicant/interworking.c

@@ -1490,7 +1490,8 @@ int interworking_home_sp_cred(struct wpa_supplicant *wpa_s,
 		mnc_len = wpa_s->mnc_len;
 	}
 #endif /* CONFIG_PCSC */
-	if (imsi && build_root_nai(nai, sizeof(nai), imsi, mnc_len, 0) == 0) {
+	if (domain_names &&
+	    imsi && build_root_nai(nai, sizeof(nai), imsi, mnc_len, 0) == 0) {
 		realm = os_strchr(nai, '@');
 		if (realm)
 			realm++;
@@ -1502,7 +1503,7 @@ int interworking_home_sp_cred(struct wpa_supplicant *wpa_s,
 	}
 #endif /* INTERWORKING_3GPP */
 
-	if (cred->domain == NULL)
+	if (domain_names == NULL || cred->domain == NULL)
 		return 0;
 
 	wpa_printf(MSG_DEBUG, "Interworking: Search for match with "