acpi: fix acpi_os_read_pci_configuration() misuse of raw_pci_read()

The raw_pci_read() interface (as the raw_pci_ops->read() before it)
unconditionally fills in a 32-bit integer return value regardless of the
size of the operation requested.

So claiming to take a "void *" is wrong, as is passing in a pointer to
just a byte variable.

Noticed by pageexec when enabling -fstack-protector (which needs other
patches too to actually work, but that's a separate issue).

Acked-by: Len Brown <len.brown@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>