Commit 4d961538f6 added libutil to the iproute2 InstallDev section
but lead to compile issues with packages picking up the wrong libutil
since libutil is quite a generic name ...
Further libutil is rather meant for internal usage in iproute2 than a
public API; therefore let's remove it from the InstallDev section together
with ll_map.h
Signed-off-by: Hans Dedecker <dedeckeh@gmail.com>
e0fbf62821