Enforce profile password quality policy on unified device lock

Effectively revert I59354066dafb02fe1d464fd1ddabf3969a4d0f1b to
allow password quality policy set on the profile DPM instance to
be enforced on device lockscreen provided the device has no
separate work challenge.

Bug: 182561862
Test: atest FrameworksServicesTests:DevicePolicyManagerTest
Test: atest ManagedProfilePasswordTest
Test: atest MixedManagedProfileOwnerTest#testResetPasswordWithToken
Test: Create work profile, set profile password quality policy,
      update device password via Settings and verify policy is applied.

Change-Id: I160997822f57c1da9327fe1a5482f445df8e1094