security/zeek: Clean up USES=python

• While I'm here, fix PLIST

> Checking for pkg-plist issues (check-plist)

> Parsing plist

> Checking for items in STAGEDIR missing from pkg-plist

Error: Orphaned: @dir lib/%%ZEEKUSER%%/plugins
Error: Orphaned: @dir lib/%%ZEEKUSER%%/spicy

> Checking for items in pkg-plist which are not in STAGEDIR

> Error: Plist issues found.

• Error code 1

Approved by: portmgr (blanket)
With hat: python