net-mgmt/unifi5: Update to 5.4.11

MASTER_SITES altered as they are publishing the beta url instead of the normal release
url

Add a new variable BUNDLEDFW to help reduce unnecessary plist churn

Changelog:
https://community.ubnt.com/t5/UniFi-Updates-Blog/UniFi-5-4-11-Stable-Candidate-has-been-released/ba-p/1825788