Change pci_raw_ops to pci_raw_read/write

We want to allow different implementations of pci_raw_ops for standard
and extended config space on x86.  Rather than clutter generic code with
knowledge of this, we make pci_raw_ops private to x86 and use it to
implement the new raw interface -- raw_pci_read() and raw_pci_write().

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>