primops: Mark actions evaluated by `catch*` as lazy

There is something very peculiar about the `catch` family of operations
with respect to strictness analysis: they turn divergence into
non-divergence. For this reason, it isn't safe to mark them as strict in
the expression whose exceptions they are catching. The reason is this:

Consider,

    let r = \st -> raiseIO# blah st
    in catch (\st -> ...(r st)..) handler st

If we give the first argument of catch a strict signature, we'll get a
demand 'C(S)' for 'r'; that is, 'r' is definitely called with one
argument, which indeed it is. The trouble comes when we feed 'C(S)' into
'r's RHS as the demand of the body as this will lead us to conclude that
the whole 'let' will diverge; clearly this isn't right.

This is essentially the problem in #10712, which arose when
7c0fff41789669450b02dc1db7f5d7babba5dee6 marked the `catch*` primops as
being strict in the thing to be evaluated. Here I've partially reverted
this commit, again marking the first argument of these primops as lazy.

Fixes #10712.

Test Plan: Validate checking `exceptionsrun001`

Reviewers: simonpj, austin

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D1616

GHC Trac Issues: #10712, #11222

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