[SCSI] arcmsr: Fix hardware wait loops

Remove _interruptible, since receiving a signal while waiting on a
hardware condition will simply cause the driver to busy-wait.

Using msleep_interruptible() is rarely the right thing to do, when
waiting on a hardware condition to change.

Also, replace msleep with ssleep while doing this, where appropriate.

[jejb: fix up merge conflict]

Signed-off-by: Jeff Garzik <jeff@garzik.org>
Acked-by: Nick Cheng <nick.cheng@areca.com.tw>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>