Usage of PKG_NAME was a bug carried over from the original code
during refactoring. Since none of the addons set PKG_SECTION, and
therefore PKG_NAME and PKG_ADDON_ID were identical, this wasn't
noticed before.
Drop using PKG_NAME and only use PKG_ADDON_ID to fix this,
install_binary_addon can then also be used for addons which set
PKG_SECTION.
Signed-off-by: Matthias Reichl <hias@horus.com>