Some notes:
1. I put in both a swiftpm like test case and a library evolution test case. I
also updated the moveonly_deinit serialization swift test to show that we
actually serialize the deinit.
2. I changed when we emit the deinit table to only be when we have a type with
an actual value type destructor. Notably this doesn't include classes today so
as a side-effect, we no longer attempt to devirtualize moveonly class deinits.
This doesn't affect anything we are trying to actually do since we do not
support noncopyable classes today. With that in mind, I changed one test that
was showing that deinit devirtualization worked to use a struct with deinit
instead of a class.
rdar://109679168
