Some late additions to DWARF v5 were not in Dwarf.def; also one form was redefined.
Add the new cases to relevant switches in different parts of LLVM.
Replace DW_FORM_ref_sup with DW_FORM_ref_sup[4,8].
I did not add support for DW_FORM_strx3 or DW_FORM_addrx3 other than defining the constants. We don't have any infrastructure to support these.
might be nice at some point to make HANDLE_DW_TAG take a 3rd parameter that is the DWARF version that it is introduced in:
Then code could actually enforce the validity of the DWARF tag for the current DWARF version.