Fix #8696 - don't generate static intra-package references.

See the comments in Packages.lhs and the ticket for some more explanation.

This is a temporary fix while we consider a way to re-enable intra-package
references in the mean time.

Authored-by: Reid Barton <rwbarton@gmail.com>
Signed-off-by: Austin Seipp <austin@well-typed.com>