Add app-callbacks for app-specific initialisation of SRIOV.
Disabling SRIOV is brought forward in nfp_pci_remove()
so that nfp_app_sriov_disable is called while the app still exists.
This is intended to be used to implement representor netdevs for virtual
ports.
Signed-off-by: Simon Horman <simon.horman@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>