pci_get_bus_and_slot() is restrictive such that it assumes domain=0 as
where a PCI device is present. This restricts the device drivers to be
reused for other domain numbers.

Getting ready to remove pci_get_bus_and_slot() function in favor of
pci_get_domain_bus_and_slot().

Add domain parameter to CDV_MSG_READ32, CDV_MSG_WRITE32, MRST_MSG_READ32,
MRST_MSG_WRITE32, MDFLD_MSG_READ32, MDFLD_MSG_WRITE32.

Extract pci_dev from struct drm_device and use pdev to find the domain
number while calling pci_get_domain_bus_and_slot().
Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
Signed-off-by: Bjorn Helgaas <helgaas@kernel.org>