dt-bindings: gpio: aspeed,sgpio: Support ast2700

dt-bindings: gpio: aspeed,sgpio: Support ast2700

The AST2700 is the 7th generation SoC from Aspeed, featuring two SGPIO
master controllers: both with 256 serial inputs and outputs.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Reviewed-by: Linus Walleij <linusw@kernel.org>
Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com>
Link: https://lore.kernel.org/r/20260123-upstream_sgpio-v2-5-69cfd1631400@aspeedtech.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>