package/docker-containerd: fix typo in uclibc dependency

Commit 6e3f7fbc ("package/runc: add
upstream security fix for CVE-2019-5736") added a dependency of
docker-containerd to uclibc (inherited from runc), but the depends on
has a typo that makes it ineffective. Due to this, docker-containerd
can still be selected in uClibc configurations, causing runc to be
build, and failing to build due fexecve() being missing in uClibc.

Fixes:

  http://autobuild.buildroot.net/results/64ecdb1e007106fdb05979b10b42b90591255504/



Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>