/usr/include/ is in libavahi-common-dev 0.6.32~rc+dfsg-1ubuntu2.3.
This file is owned by root:root, with mode 0o755.
..
/usr/include/avahi-common/
/usr/include/avahi-common/gccmacro.h
/usr/include/avahi-common/address.h
/usr/include/avahi-common/error.h
/usr/include/avahi-common/watch.h
/usr/include/avahi-common/rlist.h
/usr/include/avahi-common/cdecl.h
/usr/include/avahi-common/malloc.h
/usr/include/avahi-common/defs.h
/usr/include/avahi-common/strlst.h
/usr/include/avahi-common/timeval.h
/usr/include/avahi-common/alternative.h
/usr/include/avahi-common/simple-watch.h
/usr/include/avahi-common/llist.h
/usr/include/avahi-common/domain.h
/usr/include/avahi-common/thread-watch.h