[ofw] Add Assert to debug BS while deleting WDF device

[Hefty, Sean]

> We need to be sure that any patch is fixing the underlying issue.  What
> WdfOjbectDelete() call caused the crash?  Is it coming from one of the
> error handling sections(e.g. WmcreateControlDevice)?
> [Uri Habusha] the BS came from calling WmPowerD0Exit.

Okay - so the patch isn't actually a fix, you're just trying to catch the problem.  If we already have a blue screen, why can't we just use the backtrace from that to debug the issue?  Do you have that stack trace available to post to the list?