[RADEON]: Fix unaligned I/O port access during probe.
The driver does a readl() on DEVICE_ID which is 2-byte aligned and 2-bytes in size. It's doing this read just to flush write buffers. Create IN16() and OUT16() macros, and use the former to do this I/O load. Signed-off-by: David S. Miller <firstname.lastname@example.org>