ddns-scripts: allow setting CloudFlare 'rec_id' in the config

This is necessary when there are multiple records for the same domain,
otherwise the script will overwrite the first one returned by the API.
It has the secondary benefit of allowing faster updates by performing
only one API call instead of two.

In case 'rec_id' is not set the script behaves exactly as before.

Signed-off-by: Leonardo Brondani Schenkel <leonardo@schenkel.net>

net/ddns-scripts/files/update_CloudFlare.sh

@@ -57,6 +57,7 @@ cleanup() {
 	sed -i "#'##g" $DATFILE				# remove "'" (single quote)
 }
 
+[ -n "$rec_id" ] && __RECID="$rec_id" || {
 	# build url according to cloudflare client api at https://www.cloudflare.com/docs/client-api.html
 	# to "rec_load_all" to detect rec_id needed for update
 	__URL="https://www.cloudflare.com/api_json.html"	# https://www.cloudflare.com/api_json.html
@@ -106,6 +107,7 @@ done
 	json_get_var __RECID "rec_id"	# last thing to do get rec_id
 	json_cleanup			# cleanup
 	write_log 7 "rec_id '$__RECID' detected for host/domain '$domain'"
+}
 
 # build url according to cloudflare client api at https://www.cloudflare.com/docs/client-api.html
 # for "rec_edit" to update IP address