uuidd: do not drop privileges

uuidd: do not drop privileges

libuuid can (for now) spawn uuidd on-demand. To support this scenario,
uuidd should be installed setuid/setgid to have access to
/var/lib/libuuid/clock.txt. Therefore, dropping the privileges is
not functional, so removing this ability.

Moreover, the ability to spawn uuidd on-demand will be removed anyway.

References: http://www.spinics.net/lists/util-linux-ng/msg05934.html

Signed-off-by: Petr Uzel <petr.uzel@suse.cz>