[SCSI] ESP: Revert ESP_BUS_TIMEOUT back down to 250

This reverts d73f5222

The bug that made us increase ESP_BUS_TIMEOUT to 275 turned out to be
a memset bug on 32-bit sparc.

It is better to put this back at the correct timeout value than to
leave it increased when there is no reason for doing so.

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>