When splitting the flavours of a module into the extras and base
package, we already run depmod. Unfortunately this only produces
warnings when modules in the base package have unresolved depen-
dencies.
This change will abort the build in that case, so we can fix things.

BugLink: http://bugs.launchpad.net/bugs/1166197Signed-off-by: Stefan Bader <stefan.bader@canonical.com>