This recipe inherits nopackages but has a non-empty PACKAGES which confuses
the archiver class when:
INHERIT += "archiver"
ARCHIVER_MODE[srpm] = "1"
Ensuring PACKAGES is empty removes the errors that occur in this configuration.
[YOCTO #11121]
(From OE-Core rev: b8a603d3f1d3adac41d042e42a2283b7fdf2ae7c)
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>