libqb test suite leaves empty directories in /dev/shm

[chrissie-c]

The libqb test suite (resources.test) cleans out all the ringbuffer files left over by the deliberately failing ipc tests, but does not clean out the directories that contain them, cluttering up /dev/shm and using up inodes

resources.test should look at the parent directories of the leftover files and remove those too.

[chrissie-c]

pr #467 should clear these up