[SCSI] sym53c8xx: PCI Error Recovery support

This patch adds the PCI error recovery callbacks to the Symbios SCSI device
driver.  It includes support for First Failure Data Capture.

Signed-off-by: Linas Vepstas <linas@austin.ibm.com>

Assorted changes to initial patches, including returning IRQ_NONE from the
interrupt handler if the device is offline and re-using the eh_done completion
in the scsi error handler.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>