P2P: Write p2p_ignore_shared_freq to configuration file on updates

Commit b277a2bebc9365ec7db444d51e34aab6d1b48e63 added a new global
configuration parameter, but forgot to update configuration file saving
to store this.

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

wpa_supplicant/config_file.c

@@ -917,6 +917,9 @@ static void wpa_config_write_global(FILE *f, struct wpa_config *config)
 	if (config->p2p_no_group_iface)
 		fprintf(f, "p2p_no_group_iface=%u\n",
 			config->p2p_no_group_iface);
+	if (config->p2p_ignore_shared_freq)
+		fprintf(f, "p2p_ignore_shared_freq=%u\n",
+			config->p2p_ignore_shared_freq);
 #endif /* CONFIG_P2P */
 	if (config->country[0] && config->country[1]) {
 		fprintf(f, "country=%c%c\n",