Current code missed the Prog IF register. All Class Code, Subclass,
and Prog IF registers are needed to identify the accurate device type.
For example: USB controllers use the PROG IF for denoting: USB
FullSpeed, HighSpeed or SuperSpeed.
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com> Reviewed-by: Thomas Huth <thuth@redhat.com> Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Alexander Graf <agraf@suse.de>