DT properties which can have multiple entries need to specify what the
entries are and define how many entries there can be. In the case of
only a single entry, just 'maxItems: 1' is sufficient.

Add the missing entry constraints. These were found with a modified
meta-schema. Unfortunately, there are a few cases where the size
constraints are not defined such as common bindings, so the meta-schema
can't be part of the normal checks.

Cc: Jens Axboe <axboe@kernel.dk>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: MyungJoo Ham <myungjoo.ham@samsung.com>
Cc: Chanwoo Choi <cw00.choi@samsung.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Sebastian Reichel <sre@kernel.org>
Cc: Ohad Ben-Cohen <ohad@wizery.com>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Sebastian Reichel <sre@kernel.org>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> #for-iio
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Reviewed-by: Suman Anna <s-anna@ti.com>
Acked-by: Paul Cercueil <paul@crapouillou.net>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20210104230253.2805217-1-robh@kernel.orgSigned-off-by: Rob Herring <robh@kernel.org>