bnx2x: NAPI and interrupts enable/disable

Fixing the order of enabling and disabling NAPI and the interrupts

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