scsi: mpt3sas: Add sysfs to know supported features

Currently with sysfs parameter "drv_support_bitmap" driver exposes whether
driver supports toolbox memory move command or not.

And application should issue the toolbox memory move command only if driver
tell that memory move tool box command is supported through this sysfs
parameter.

In future we can utilize this sysfs parameter if any new feature is added
and need to notify the same to applications.

Signed-off-by: Suganath Prabu <suganath-prabu.subramani@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>