nvmem: imx-ocotp: replace global post processing with layouts

nvmem: imx-ocotp: replace global post processing with layouts

In preparation of retiring the global post processing hook change this
driver to use layouts. The layout will be supplied during registration
and will be used to add the post processing hook to all added cells.

Signed-off-by: Michael Walle <michael@walle.cc>
Tested-by: Michael Walle <michael@walle.cc> # on kontron-pitx-imx8m
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20230404172148.82422-19-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>