When implementing Strict Haskell, the patch 46a03fbe didn't faithfully
implement the semantics given in the manual. In particular there was
an ad-hoc case in mkSelectorBinds for "strict and no binders" that
didn't work.

This patch fixes it, curing Trac #11572.

Howver it forced me to think about banged let-bindings, and I rather
think we do not have quite the right semantics yet, so I've opened
Trac #11601.