/usr/ is in libdfu-dev 0.7.0-0ubuntu4.
This file is owned by root:root, with mode 0o755.
..
/usr/include/libdfu/dfu-target.h
/usr/include/libdfu/dfu-element.h
/usr/include/libdfu/dfu-common.h
/usr/lib/
/usr/lib/x86_64-linux-gnu/
/usr/lib/x86_64-linux-gnu/pkgconfig/
/usr/lib/x86_64-linux-gnu/pkgconfig/dfu.pc
/usr/include/
/usr/include/dfu.h
/usr/include/libdfu/
/usr/include/libdfu/dfu-image.h
/usr/include/libdfu/dfu-device.h
/usr/include/libdfu/dfu-error.h
/usr/include/libdfu/dfu-context.h
/usr/include/libdfu/dfu-firmware.h
/usr/include/libdfu/dfu-sector.h
/usr/share/
/usr/share/gir-1.0/
/usr/share/gir-1.0/Dfu-1.0.gir
/usr/share/doc/
/usr/share/doc/libdfu-dev/
/usr/share/doc/libdfu-dev/copyright
/usr/lib/x86_64-linux-gnu/libdfu.so
/usr/share/doc/libdfu-dev/changelog.Debian.gz