recoverd: LCP2 cleanups

recoverd: LCP2 cleanups

* Remove unnecessary candimbl parameter.

  This parameter can be cheaply calculated in
  lcp2_failback_candidate().  The compiler will probably do an
  excellent job optimising it.  :-)

* Clarify a debug statement

  This is much clearer than doing a complex recalculation of a known
  value.

Signed-off-by: Martin Schwenke <martin@meltin.net>
Reviewed-by: Amitay Isaacs <amitay@gmail.com>
(Imported from commit 24b734f084de36160d065dc639100eab3b186f6c)