mtd: nand: Wait tCCS after a column change

Drivers implementing ->cmd_ctrl() and relying on the default ->cmdfunc()
implementation usually don't wait tCCS when a column change (RNDIN or
RNDOUT) is requested.
Add an option flag to ask the core to do so (note that we keep this as
an opt-in to avoid breaking existing implementations), and make use of
the ->data_interface information is available (otherwise, wait 500ns).

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Tested-by: Marc Gonzalez <marc_gonzalez@sigmadesigns.com>