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Sometimes, Yocto will not copy the files to the deploy directory, even if you specify "-fc deploy". The reason is not known. In this case, if you want to be certain your modified Device Tree has been build and copied, you can do these steps below which rebuild the entire kernel (but will will 100% of the time).
bitbake linux-kernelrenesas -fc compile bitbake linux-kernelrenesas -fc deploy
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