mem-cache: Use secure bit in findVictim

mem-cache: Use secure bit in findVictim

Sector caches must know if there was a sector hit in order
to decide whether a victim's sector must be fully evicted
to give place to a new sector or not.

In order to do so it needs the tag and secure information.

Change-Id: Ib554169e25fa131d6bf986561f7970b787c56874
Reviewed-on: https://gem5-review.googlesource.com/10722
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>