Make the SPI framework and drivers stop using class_device.  Update docs
accordingly ...  highlighting just which sysfs paths should be
"safe"/stable.
Signed-off-by: NTony Jones <tonyj@suse.de>
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>