dt-bindings: Fix 'enum' lists with duplicate entries

There's no reason to list the same value twice in an 'enum'. Fix all the
occurrences in the tree. A meta-schema change will catch future ones.

Cc: Krzysztof Kozlowski <krzk+dt@kernel.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Charles Keepax <ckeepax@opensource.cirrus.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Sebastian Reichel <sre@kernel.org>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Yunfei Dong <yunfei.dong@mediatek.com>
Cc: - <patches@opensource.cirrus.com>
Cc: linux-media@vger.kernel.org
Cc: alsa-devel@alsa-project.org
Cc: linux-gpio@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20220401141247.2993925-1-robh@kernel.org