mtd: rawnand: timings: Provide onfi_fill_data_interface() with a data interface

Right now the core uses onfi_fill_data_interface() to initialize the
nand_data_interface object embedded in nand_chip, but we are about to
allocate this object dynamically and let manufacturer drivers provide
their own interface config. Let's patch the onfi_fill_data_interface()
so it can initialize an interface config that's not the one
currently attached to the nand_chip.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://lore.kernel.org/linux-mtd/20200529111322.7184-14-miquel.raynal@bootlin.com