-----------------------------------
	Correct a horrible error in repType
	-----------------------------------

repType is meant to give the underlying representation of a type.
But it wasn't taking account of the fact that *recursive* newtypes are
still represented by a TyConApp.  (Non-recursive ones behave much more
like type synonyms now.)

As a result, if we have

	newtype F = F (F->F)

then Bad Things happen if we try to seq x::F.  We decide whether to
push an ordinary return address or a SEQ frame based on the type,
and repType didn't expose the fact that F is represented by a function type.

Aargh. codeGen/should_run/cg050 now tests for this.