It is caused by both
MAPREDUCE-3199 and MAPREDUCE-3003. Once the parent artifact for all the modules got changed to hadoop-project via MAPREDUCE-3003, most of the mapreduce/yarn modules lost hold of the log4j configuration. MAPREDUCE-3199 worsened it for every module.
The attached patch should work.
The alternative is to set the hard-coded location of log4j.properties in each module, which won't be maintainable. Even relative links like maven.project.parent.* also break over time as was found after