dt-bindings: pinctrl: mediatek,pinctrl-mt6795: Improve interrupts description

Clarify the meaning of sysirq to avoid confusion.

Suggested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Yassine Oudjana <y.oudjana@protonmail.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20221028153505.23741-7-y.oudjana@protonmail.com


Signed-off-by: Linus Walleij <linus.walleij@linaro.org>