Remove unused GeneratorTarget.
Merge topic 'fix-automoc-compile-defs' into next

7264f0b Remove unused GeneratorTarget.
Fix TARGET_PROPERTY target extractions.

We need to make sure we can export targets which have content such
as $<0:$<TARGET_PROPERTY:not_a_target,INTERFACE_INCLUDE_DIRECTORIES>

That means making not finding a target non-fatal here.
Merge topic 'fix-TARGET_PROPERTY-extraction' into next

cf07469 Fix TARGET_PROPERTY target extractions.
Fix typo.
Merge topic 'fix-TARGET_PROPERTY-extraction' into next

9680e6b Fix typo.