ssa_db: add 'data_tbl_cnt' counter to 'ssa_db' structure

Signed-off-by: Ilya Nelkenbaum <ilyan@mellanox.com>
Signed-off-by: Hal Rosenstock <hal@mellanox.com>
ssa_db.h: Cosmetic formatting change

Signed-off-by: Hal Rosenstock <hal@mellanox.com>