bnx2x: Recoverable and unrecoverable error statistics

Add statistics for tracking parity errors from which we successfully
recovered and those which were deemed unrecoverable.

Signed-off-by: Ariel Elior <ariele@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>