scsi: megaraid_sas: use adapter_type for all gen controllers

commit c365178f3147f38d26c15bdf43a363bacb5406ec upstream.

No functional change.
Refactor adapter_type to set for all generation controllers, not
just for fusion controllers.

Signed-off-by: Kashyap Desai <kashyap.desai@broadcom.com>
Signed-off-by: Shivasharan S <shivasharan.srikanteshwara@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>