arm64: dts: qcom: msm8998-fxtec: Use "okay" instead of "ok"

This is the standard way.

Signed-off-by: Konrad Dybcio <konrad.dybcio@somainline.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220430162353.607709-9-konrad.dybcio@somainline.org