For the rationale to allow this, see commit
a66c73deef
This was broken when cuckoo hashing was added, and
subtly broke (for example) lichess' Android application,
thus illustrating the original judgement was sound.
No functional change.
Stockfish currently relies on the "filter_root_moves" function also
having the side effect of clamping Cardinality against MaxCardinality
(the actual piece count in the tablebases). So if we skip this function,
we will end up probing in the search even without tablebases installed.
We cannot bail out of this function before this check is done, so move
the MultiPV hack a few lines below.
A band-aid patch to workaround current TB code
limitations with multi PV.
Hopefully this will be removed after committing the
big update of TB impementation, now under discussion.
No functional change.
