bnx2x: Disabling interrupts after iSCSI-boot

Before initializing the chip after iSCSI boot, the interrupts of the function
that was used to boot must be disabled. That means that the driver needs to set
the chip as if it is the iSCSI PCI function - this bug is exposed only with MSI

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