ptest: allow the ptest-packagelists.inc warning to be disabled
ptest.bbclass has a sanity check that all recipes in oe-core which
inherit ptest are also listed in the ptest-packagelists.inc file, and
the build fails if this is not the case.
Whilst this is a laudable goal, it is over-zealous as if the recipe has
a bbappend in another layer which inherits ptest, the build will fail.
By changing the combination of anonymous Python and bb.error() to a
recipe-scope QA test, this can be handled with the other sanity checks
and bbappends can skip the test if desired.
Signed-off-by: Ross Burton <ross.burton@arm.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
