Genex: Make CMP0021 and CMP0022 usable with TARGET_POLICY

Use preprocessor loops and add a unit test for the appropriate
policies. All policies whose value is recorded at target creation
time should be part of this list.
Merge topic 'target-policies' into next

cf1eeb5 Genex: Make CMP0021 and CMP0022 usable with TARGET_POLICY