Sepolicy: Allow everyone to search keyrings

Allow everyone to look for keys in the fsverity keyring. This is
required to access fsverity-protected files, at all.

This set of permissions is analogous to allowances for the fscrypt
keyring and keys.

Bug: 125474642
Test: m
Test: manual
Change-Id: I6e8c13272cdd76d9940d950e9dabecdb210691b1
5 files changed