privacy-hub: Add GoogleLocationServicesEnabled policy

Add GoogleLocationServicesEnabled user policy that's tied to the
`kUserGeolocationAccessLevel` pref. Admin will be able to force-set the
value of system geolocation setting to:
- Blocked
- Allowed
- Only allowed for system services
Or leave the policy unset to let users decide.

This policy will replace ArcGoogleLocationServicesEnabled policy and remove ARC hook for DefaultGeolocationSetting policy. These
will come in a follow-up CL.

Bug: b:298172164
Test: testing/xvfb.py out/Default/browser_tests --gtest_filter=*PrivacyHubPolicyTest*

Change-Id: I1dd1974e3ae377e3fb72cae6c1802e08ddbc0228
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5245572
Reviewed-by: Maksim Ivanov <emaxx@chromium.org>
Commit-Queue: Zauri Meshveliani <zauri@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1258430}