nvmem: rockchip-otp: Move read-offset into variant-data

[ Upstream commit 6907e809 ]

The RK3588 has an offset into the OTP area where the readable area begins
and automatically adds this to the start address.
Other variants are very much similar to rk3588, just with a different
offset, so move that value into variant-data.

To match the size in bytes, store this value also in bytes and not in
number of blocks.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20250411112251.68002-2-srinivas.kandagatla@linaro.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>