config: Add bgscan option when saving global configuration

Signed-off-by: Alexander Bondar <alexander.bondar@intel.com>

wpa_supplicant/config_file.c

@@ -1118,6 +1118,9 @@ static void wpa_config_write_global(FILE *f, struct wpa_config *config)
 	if (config->tdls_external_control)
 		fprintf(f, "tdls_external_control=%d\n",
 			config->tdls_external_control);
+
+	if (config->bgscan)
+		fprintf(f, "bgscan=\"%s\"\n", config->bgscan);
 }
 
 #endif /* CONFIG_NO_CONFIG_WRITE */