base: Add a perfect bloom filter

Add a bloom filter that keeps track of all observed entries, and
thus has no false negatives nor false positives.

Change-Id: Iba784e617a99c77554c688470d9b9e12c260f23b
Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18879
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>