control: Stop caching uninteresting service ifaces

In the code that adds the path/service/interface to the services cache,
there was one code path that would add every interface on the path to
the cache map instead of just the service being requested.  Change the
code to only add that single interface.

Signed-off-by: Matt Spinler <spinler@us.ibm.com>
Change-Id: I5c3d03d2855c4506dcf58fd1d805f1ec9ae3c25a
1 file changed