When no option is passed to getdelays it just hangs, waiting
for a reply which will never come.

This patch prints usage() when no output marker is specified.
Signed-off-by: NMarcus Meissner <meissner@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>