pci: Add Apple PCIe controller driver

This driver supports the PCIe controller on the Apple M1 and
M2 SoCs.  The code is adapted from the Linux driver.

Signed-off-by: Mark Kettenis <kettenis@openbsd.org>
diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile
index dd1ad91..d393f1b 100644
--- a/drivers/pci/Makefile
+++ b/drivers/pci/Makefile
@@ -13,6 +13,7 @@
 
 obj-$(CONFIG_PCIE_ECAM_GENERIC) += pcie_ecam_generic.o
 obj-$(CONFIG_PCIE_ECAM_SYNQUACER) += pcie_ecam_synquacer.o
+obj-$(CONFIG_PCIE_APPLE) += pcie_apple.o
 obj-$(CONFIG_PCI_GT64120) += pci_gt64120.o
 obj-$(CONFIG_PCI_MPC85XX) += pci_mpc85xx.o
 obj-$(CONFIG_PCI_MSC01) += pci_msc01.o