dt-bindings: Fix typo in comment

Fix typo in the comment

Signed-off-by: Slark Xiao <slark_xiao@163.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220721011746.19663-1-slark_xiao@163.com

gpio: Add generic serializer DT binding

Add binding for generic parallel-in/serial-out shift register devices
used as GPIO.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Acked-by: Rob Herring <robh@kernel.org>
[Clarified ngpios semantic]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>