More usages of pmap_ptedinhash().

More usages of pmap_ptedinhash().

If you wonder why pte_insert{32,64}() is not using pmap_hash_remove() if
it finds a conflicting PTE in the HASH, it's because in the current state
trying to grab the same lock a second time would lead to a deadlock.

This is much easier to reproduce on G5 (or G4 with BAT disabled).

ok kettenis@, deraadt@, dlg@