dt-bindings: mfd: x-powers,axp152: Simplify disallowing properties

The syntax to disallow x-powers,drive-vbus-en,
x-powers,self-working-mode and x-powers,master-mode for certain variants
can be made simpler.  Also this produces much nicer warning message when
the condition hits wrong DTS.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Tested-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230325114353.50293-1-krzysztof.kozlowski@linaro.org