x86/ia64: intel-iommu: move to drivers/iommu/

This should ease finding similarities with different platforms,
with the intention of solving problems once in a generic framework
which everyone can use.

Note: to move intel-iommu.c, the declaration of pci_find_upstream_pcie_bridge()
has to move from drivers/pci/pci.h to include/linux/pci.h. This is handled
in this patch, too.

As suggested, also drop DMAR's EXPERIMENTAL tag while we're at it.

Compile-tested on x86_64.

Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
diff --git a/include/linux/pci.h b/include/linux/pci.h
index c446b5c..970bfe0 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1589,5 +1589,16 @@
 int pci_vpd_find_info_keyword(const u8 *buf, unsigned int off,
 			      unsigned int len, const char *kw);
 
+/**
+ * pci_find_upstream_pcie_bridge - find upstream PCIe-to-PCI bridge of a device
+ * @pdev: the PCI device
+ *
+ * if the device is PCIE, return NULL
+ * if the device isn't connected to a PCIe bridge (that is its parent is a
+ * legacy PCI bridge and the bridge is directly connected to bus 0), return its
+ * parent
+ */
+struct pci_dev *pci_find_upstream_pcie_bridge(struct pci_dev *pdev);
+
 #endif /* __KERNEL__ */
 #endif /* LINUX_PCI_H */