dt-bindings: Fix unbalanced quotation marks

Multiple binding documents have various forms of unbalanced quotation
marks. Fix them.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Rob Herring <robh@kernel.org>