d: Fix ICE: type variant differs by TYPE_MAX_VALUE with -g [PR119826]

d: Fix ICE: type variant differs by TYPE_MAX_VALUE with -g [PR119826]

Forward referenced enum types were never fixed up after the main
ENUMERAL_TYPE was finished.  All flags set are now propagated to all
variants after its mode, size, and alignment has been calculated.

	PR d/119826

gcc/d/ChangeLog:

	* types.cc (TypeVisitor::visit (TypeEnum *)): Propagate flags of main
	enum types to all forward-referenced variants.

gcc/testsuite/ChangeLog:

	* gdc.dg/debug/imports/pr119826b.d: New test.
	* gdc.dg/debug/pr119826.d: New test.