mm/memory: Use ptep_get_lockless_norecency() for orig_pte

Let's convert handle_pte_fault()'s use of ptep_get_lockless() to
ptep_get_lockless_norecency() to save orig_pte.

There are a number of places that follow this model:

    orig_pte = ptep_get_lockless(ptep)
    ...
    <lock>
    if (!pte_same(orig_pte, ptep_get(ptep)))
            // RACE!
    ...
    <unlock>

So we need to be careful to convert all of those to use
pte_same_norecency() so that the access and dirty bits are excluded from
the comparison.

Additionally there are a couple of places that genuinely rely on the
access and dirty bits of orig_pte, but with some careful refactoring, we
can use ptep_get() once we are holding the lock to achieve equivalent
logic.

Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>