CODEOWNERS: add code owners to dts/arm/nuvoton/

Move @MulinChao, @WealianLiao, and myself from code owners entry
dts/arm/nuvoton/npcx to dts/arm/nuvoton.
So we will be chosen as reviewers automatically when dtsi files under
dts/arm/nuvoton are touched.

Signed-off-by: Jun Lin <CHLin56@nuvoton.com>
1 file changed