Fix a possible crash in excluded search condition

Fix a possible crash in excluded search condition

Due to IID we could have a ttMove and not a tte, or,
even if we have a tte they could belong to different
searches so that the depth and type of tte don't
have the same origin of the ttMove.

To fix this we always use tte entry in excluded search
condition and, after an IID, we reprobe the TT table.

No functional change. Apart from possible crash fix.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>