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>

base: Make Bloom Filter counting by default

Since a boolean bool filter is a saturating bloom filter with a
single bit per entry, generalize them by using SatCounter instead
of int for the filter entries.

Change-Id: I7f54e28d54de5671e0770b02ed9161735e6bd339
Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18877
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>

mem-ruby: Move Bloom Filters to base

All Bloom Filters are completely independent of Ruby, and
therefore can be used everywhere.

As a side effect, Ruby was not using the filters, so
their dependency was removed.

Change-Id: Ic5f430610c33c0791fb81c79101ebe737189497e
Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18875
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>