testsuite: Use ghci_ways to set ways in PackedDataCon/UnboxedTuples/UnliftedDataTypeInterp tests
These tests reimplemented the logic from valid_way in order to
determine what ways to run. It's easier to use this combination of
only_ways and extra_ways to only run in GHCi ways and always run in
GHCi ways.
Taken from !14872 (closed)