MT#7655 Fix access perms for sub(admin) in prefs

Certain preferences (those meta-prefs not coming from the prefs
table, like voicemail, fax2mail, aa, speeddial) had wrong access
fencing, preventing sub(admins) to edit them.

(cherry picked from commit 390a18b69b8d683b1029c4e9b187a3a97a9f50ca)