Placeholder DHCP user scripts were added recently.
These files make package-based installations of such scripts more difficult.
Pull user callbacks from directories instead to allow packages and users to
install co-existing scripts more easily.
References:
b4f3d93b5 odhcp6c: add a odhcp6c.user placeholder script
Signed-off-by: Leon M. George <leon@georgemail.eu>
Signed-off-by: Hans Dedecker <dedeckeh@gmail.com> [PKG_RELEASE increase]