Display default values for '-a' and '-w' command line arguments in the
usage help text.
(From OE-Core rev: 580708398f22333bc4b5899e4129a8939fb7ce12)
Signed-off-by: Markus Lehtonen <markus.lehtonen@linux.intel.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>