This patch changes the name of function cfb_blank to smtc_blank. This
function is not implemented like a generic function for frame buffer.
Having the old prefix becomes confused when reading fb_ops structs.
Tested with SM712
Signed-off-by: Javier M. Mellid <jmunhoz@igalia.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>