scsi: megaraid_sas: Do not set fp_possible if TM capable for non-RW syspdIO, change fp_possible to bool

FIX - firmware wants non-RW SYS PD IOs to avoid FastPath for better
tracking and other functionalities if the device is task management
capable.
Signed-off-by: NKashyap Desai <kashyap.desai@broadcom.com>
Signed-off-by: NShivasharan S <shivasharan.srikanteshwara@broadcom.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Reviewed-by: NTomas Henzl <thenzl@redhat.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>