[SCSI] bnx2i: fix the bit manipulation when setting the error mask

The intention in bnx2i_send_fw_iscsi_init_msg was to zero out
only the lower 32bits, but instead the whole mask64 is zeroed.
This patch fixes it.

Signed-off-by: Tomas Henzl <thenzl@redhat.com>
Acked-by: Eddie Wai <eddie.wai@broadcom.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>