Fix: kernel metadata file outside of kernel/ directory

3ef395a9, a backport of a2814ea, introduces a regression that
causes the kernel trace metadata file to be created outside of
the "kernel" domain sub-directory.

master and stable-2.12 no longer need the domain sub-directory
to be passed to the consumer daemon. However, it was still used
in the 2.11 release.

Fixes #1275

Reported-by: Christophe Bedard <bedard.christophe@gmail.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Change-Id: I1fe10ddd414cc87264b5e6d6a6d81e45ebc800d4