[SCSI] qla2xxx: Add hardware trace-logging support.

Recent ISPs have a region within FLASH which acts as a repository
for the logging of serious hardware and software failures.
Currently, the region is large enough to support up to 255
entries.

Signed-off-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>