[SCSI] aha152x_cs: Fix regression that keeps driver from using shared interrupts

At some point since 2.6.22, the aha152x_cs driver stopped working and
started erring on load with the following messages:

kernel: pcmcia: request for exclusive IRQ could not be fulfilled.
kernel: pcmcia: the driver needs updating to supported shared IRQ lines.

With the following change, the driver works with shared IRQs.

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Stable <stable@kernel.org>		[2.6.28], [2.6.27], [2.6.26]
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>