dt-bindings: interrupt-controller: migrate MIPS CPU interrupt controller text bindings to YAML

MIPS CPU interrupt controller bindings used text format, so migrate them
to YAML.

Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220921072405.610739-1-sergio.paracuellos@gmail.com


Signed-off-by: Rob Herring <robh@kernel.org>