dt-bindings: spmi: Add Apple SPMI NVMEM

Add bindings for exposing SPMI registers of Apple PMICs as NVMEM cells

Reviewed-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Signed-off-by: Sasha Finkelstein <fnkl.kernel@gmail.com>
Reviewed-by: "Rob Herring (Arm)" <robh@kernel.org>
Reviewed-by: Neal Gompa <neal@gompa.dev>
Signed-off-by: Srinivas Kandagatla <srini@kernel.org>
Link: https://lore.kernel.org/r/20250509122452.11827-3-srini@kernel.org


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