misc: pci_endpoint_test: Avoid using module parameter to determine irqtype

commit e0332712 ("pci_endpoint_test: Add 2 ioctl commands")
uses module parameter 'irqtype' in pci_endpoint_test_set_irq()
to check if IRQ vectors of a particular type (MSI or MSI-X or
LEGACY) is already allocated. However with multi-function devices,
'irqtype' will not correctly reflect the IRQ type of the PCI device.

Fix it here by adding 'irqtype' for each PCI device to show the
IRQ type of a particular PCI device.

Fixes: e0332712 ("pci_endpoint_test: Add 2 ioctl commands")
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: stable@vger.kernel.org # v4.19+