nvmem: imx-ocotp: imx8mq is compatible with imx6 not imx7

According to NXP Reference Manuals and uboot/atf sources the OCOTP block
on imx8m behaves more like imx6 than imx7.

- Fuses can be read/written 32bits at a time (no imx7-like banking)
- The OCOTP_HW_OCOTP_TIMING register is like imx6 not imx7

Since nvmem doesn't support uboot-style "sense" and "override" this
issue only affected "write" which is very rarely used.

Fixes: 163c0dbd0cb1 ("nvmem: imx-ocotp: add support for imx8mq")
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>