Ensure of_type subclass taken into account with wildcards

Ensure of_type subclass taken into account with wildcards

Fixed a regression in 1.2 where a wildcard/load_only loader option would
not work correctly against a loader path where of_type() were used to limit
to a particular subclass.  The fix only works for of_type() of a simple
subclass so far, not a with_polymorphic entity which will be addressed in a
separate issue; it is unlikely this latter case was working previously.

Since we ensure that the entity is broken out into its superclasses
when a wilcard is encountered, we can limit the entity path to the
specific entity given in this case.

Within this issue some additional issues with with_polymorphic()
loaders were found which will be addressed in #4469.

Fixes: #4468
Change-Id: Ie91ec27b49104e019636f870776e294321586a9e