mem-ruby: Define BloomFilter namespace

mem-ruby: Define BloomFilter namespace

Define a BloomFilter namespace and put all BloomFilter related
code in it.

As a side effect the BloomFilter classes have been renamed to
remove the "BloomFilter" suffix.

Change-Id: I3ee8cc225bf3b820e561c3e25a6bf38e0012e3a8
Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18874
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>