Ifdef out Linux intel_ips kludge in intel_pm.c.
Replace i915 private regs from pci_ioremap to drm_ioremap.

Replace read/write{b,l,w} by DRM_READ/WRITE{8,16,32} in i915_drv.c.
intel_ringbuffer.h needs <asm/bug.h>.
Switch intel_ring_buffers from Linux ioremap to drm_ioremap.
Fill in <linux/acpi_io.h> with acpi_os_ioremap (= AcpiOsMapMemory).

Define __acpi_iomem as an empty frotz to replace the Linux __iomem
attribute selectively and greppably.  AcpiOsMapMemory returns usable
kernel virtual addresses, so we don't need to use bus_space_mumble or
anything to dereference them.
Ifdef out field bit_algo of struct intel_gmbus.

XXX Revisit this with the rest of i2c cruft...
Add pci_config_{read,write}_dword to <linux/pci.h>.
Add <linux/ioport.h> with struct resource: keeps bus_space_alloc books.
Add pci_bus_alloc_resource to <linux/pci.h>.
Add __always_unused and round_up to <linux/kernel.h>.
Add pci_kludgey_find_dev to <linux/pci.h>.

This is not a Linux KPI, but the Linux KPI (pci_get_bus_and_slot)
doesn't pass along the original pci device or bus, so this is what
we'll use to replace uses of it (or, the one use of it) without
changing much code.
Add field to struct pci_dev for the PCI device number.
Add stubs for pci_enable_msi and pci_disable_msi to <linux/pci.h>.
Fix sense of refcount decrement conditional in drm_iounmap.

Add some kasserts just in case.
Add some consts to i915/dvo_ch7xxx.c for string literals.
Make Linux WARN_* macros expand to expressions, not statements.

These are to return the value of the condition.
Implement udelay (DELAY) and msleep (kpause) in <linux/delay.h>.
Add some conversion and comparison stuff to <linux/jiffies.h>.
Add upper_32_bits and lower_32_bits to <linux/kernel.h>.
Add THIS_MODULE (expanding to 0) to <linux/module.h>.