KickCleaner sets the out of space flag, kicks the cleaner and then waits for
that flag to clear. Only the cleaner clears it, and the cleaner returns
immediately when the cache poll interval is not positive, so when it is
disabled nothing ever reads the kick or clears the flag and the caller waits
forever.
It now returns straight away in that case, under the same condition the
cleaner itself uses to decide it is disabled. Callers already retry a bounded
number of times and then report the error, which is the right outcome when
nothing is going to free space.