dt-bindings: Drop redundant 'maxItems/minItems' in if/then schemas

Another round of removing redundant minItems/maxItems when 'items' list is
specified. This time it is in if/then schemas as the meta-schema was
failing to check this case.

If a property has an 'items' list, then a 'minItems' or 'maxItems' with the
same size as the list is redundant and can be dropped. Note that is DT
schema specific behavior and not standard json-schema behavior. The tooling
will fixup the final schema adding any unspecified minItems/maxItems.

Signed-off-by: Rob Herring <robh@kernel.org>
Acked-By: Vinod Koul <vkoul@kernel.org>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # For MMC
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> #for IIO
Link: https://lore.kernel.org/r/20220503162738.3827041-1-robh@kernel.org