bnx2x: Prevent memory leak when cnic is absent

bnx2x driver allocates searcher T2 tables, but it releases that memory
during unload only released if the cnic is loaded.

Signed-off-by: Yuval Mintz <yuvalmin@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>