PCI: endpoint: Drop PCI_EPC_IRQ_XXX definitions

PCI: endpoint: Drop PCI_EPC_IRQ_XXX definitions

linux/pci.h defines the IRQ flags PCI_IRQ_INTX, PCI_IRQ_MSI and
PCI_IRQ_MSIX. Let's use these flags directly instead of the endpoint
definitions provided by enum pci_epc_irq_type. This removes the need
for defining this enum type completely.

Link: https://lore.kernel.org/r/20231122060406.14695-3-dlemoal@kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>