I'd somehow missed the existence of fail() when I wrote these. It's
preferable here so you don't get the somewhat useless "false is not
true" message in the case of failure.
(From OE-Core rev: 173a5896fff57136e1f15e15f90961416aadde94)
Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>