scsi: mpt3sas: Capture IOC data for debugging purposes

scsi: mpt3sas: Capture IOC data for debugging purposes

Information needed to debug driver problems and firmware faults is stored
in the IOC’s MPT3SAS_ADAPTER data structure. Parameters such as IOCFacts,
IOC flags (related to sge, MSI-X, error recovery etc.), performance mode
type, TMs, internal commands reply status, etc. are present.

For debugging purposes, it is therefore helpful to be able to capture this
information so that the fault can be analyzed. Export the MPT3SAS_ADAPTER
data structure in debugfs. The data is available in:

	 /sys/kernel/debug/mpt3sas/scsi_hostX/ioc_dump

Link: https://lore.kernel.org/r/1588056322-29227-1-git-send-email-suganath-prabu.subramani@broadcom.com
Signed-off-by: Suganath Prabu <suganath-prabu.subramani@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>