mem-cache: Fix FALRU hash invalidation

mem-cache: Fix FALRU hash invalidation

The block was being invalidated before the hash could erase
its entry, therefore it was using invalid values (tag was
being assigned MaxAddr and the secure bit was reset).

This change reorders the calls, so that the appropriate hash
entry is erased.

Change-Id: I161463df0f8f5220179bc68d7be12051e5390d01
Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/13210
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>