Allow QUERY_ADMIN_POLICY holders query admins

This is to allow privileged apps like SysUI to query which admin
enforced a restriction.

Bug: 379833424
Test: TH
Flag: EXEMPT bugfix
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:b45bb48c0469d349782a2af83039b039f976d9e0)
Merged-In: I83a4d528fce4f7dd196e4623d537cf312dd18899
Change-Id: I83a4d528fce4f7dd196e4623d537cf312dd18899