scripts/oe-selftest: append metadata to tests results

scripts/oe-selftest: append metadata to tests results

Many stored results TEST_TYPE are set to "oeselftest", however all those
tests are not run with the same sets of parameters, so those tests results may
not be comparable.

Attach relevant parameters as tests metadata to allow identifying tests
configuration so we can compare tests only when they are run with the same
parameters.

Signed-off-by: Alexis Lothoré <alexis.lothore@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>