[SCSI] deprecate the old NCR53C9x driver

Now that we have the much better esp_scsi driver and low level drivers
are easy to port over deprecate the old NCR53C9x driver.

I've Cc'ed the m68k and mips lists because all but one bus glues are
for these platforms.  Chances stand bad for the remaining driver,
mca_53c9x which hasn't gotten any non-trivial update since it was
merge in late 2.1.x and whos maintainers mail address bounces.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>