Deprecate PermissionControllerManager.getPrivilegesDescriptionStringForProfile().

The strings provided by
PermissionControllerManager.getPrivilegesDescriptionStringForProfile()
are no longer used by the CDM app since Android T, so we should
deprecate it to prepare for removal.

Bug: 272129940
Test: presubmit
Change-Id: I2a0fc66b0b84854c78fbd9acf3e593806d101dad