misc: pci_endpoint_test: Populate sriov_configure ops to configure SR-IOV device

Populate sriov_configure ops with pci_sriov_configure_simple to
configure SR-IOV device.

Link: https://lore.kernel.org/r/20210819123343.1951-8-kishon@ti.com
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>