Use HsForAllTelescope to avoid inferred, visible foralls

Currently, `HsForAllTy` permits the combination of `ForallVis` and
`Inferred`, but you can't actually typecheck code that uses it
(e.g., `forall {a} ->`). This patch refactors `HsForAllTy` to use a
new `HsForAllTelescope` data type that makes a type-level distinction
between visible and invisible `forall`s such that visible `forall`s
do not track `Specificity`. That part of the patch is actually quite
small; the rest is simply changing consumers of `HsType` to
accommodate this new type.

Fixes #18235. Bumps the `haddock` submodule.

1 files changed, 0 insertions, 0 deletions

diff --git a/utils/haddock b/utils/haddock
-Subproject e2a7f9dcebc7c48f7e8fccef8643ed0928a9175
+Subproject a1cc87c864242377833ab383f1df72583ab4a01