nvmem: Add R-Car E-FUSE driver

R-Car Gen4 SoCs contain fuses indicating hardware support or hardware
(e.g. tuning) parameters.  Add a driver to access the state of the
fuses.  This supports two types of hardware fuse providers:
  1. E-FUSE non-volatile memory accessible through the Pin Function
     Controller on R-Car V3U and S4-8,
  2. E-FUSE non-volatile memory accessible through OTP_MEM on R-Car V4H
     and V4M.

The state of the cells can be read using the NVMEM framework, either
from kernel space (e.g. by the Renesas UFSHCD driver), or from
userspace.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20241030140315.40562-3-srinivas.kandagatla@linaro.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>