dt-bindings: sram: sunxi-sram: Add regulators child

Some sunxi SoCs have in-package regulators controlled by a register in
the system control MMIO block. Allow a child node for this regulator
device in addition to SRAM child nodes.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20240622150731.1105901-2-wens@kernel.org


Signed-off-by: Chen-Yu Tsai <wens@csie.org>