The writer always printed the script was written even if this
was not the case when specififying '--json-only'.
(From OE-Core rev: b2efb4c6c8bd938aac5146e14bd0c38f3f632bc4)
Signed-off-by: Jermain Horsman <jermain.horsman@nedap.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>