Self-tests following boot from SAN have failed as the
UNDI driver might leave some NIG interrupt indications.

This patch does the clean-up, clearing those indications
and allowing the test to pass.
Signed-off-by: NYuval Mintz <yuvalmin@broadcom.com>
Signed-off-by: NAriel Elior <ariele@broadcom.com>
Signed-off-by: NEilon Greenstein <eilong@broadcom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>