Prevents crash in signing if GPG_PATH is defined.
(From OE-Core rev: 0ecd748258abfe5ed9e9e2505aeb42b232389968)
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>