Hints for ethtool in main

Hints

• asv-summary-first-word-not-capitalized
  org.kernel.software.network.ethtool.metainfo.xml:6 -
  The summary text does not start with a capitalized word, project name or number.
• asv-content-rating-missing
  org.kernel.software.network.ethtool.metainfo.xml -
  This component has no `content_rating` tag to provide age rating information. You can generate the tag data online by answering a few questions at https://hughsie.github.io/oars/
• asv-developer-info-missing
  org.kernel.software.network.ethtool.metainfo.xml -
  This component contains no `developer` element with information about its author.