oeqa/selftest/oescripts: Ensure buildstats is present

These tests need buildstats to be configured. Add that piece of
config in case it isn't by default.

(From OE-Core rev: d1962257783ed9348be9fdd2db20b7d2b7c37ce1)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/lib/oeqa/selftest/cases/oescripts.py

@@ -18,6 +18,10 @@ class OEPybootchartguyTests(OESelftestTestCase):
     @classmethod
     def setUpClass(cls):
         super().setUpClass()
+        cls.write_config(cls,
+"""
+INHERIT += "buildstats"
+""")
         bitbake("core-image-minimal -c rootfs -f")
         cls.tmpdir = get_bb_var('TMPDIR')
         cls.buildstats = cls.tmpdir + "/buildstats/" + sorted(os.listdir(cls.tmpdir + "/buildstats"))[-1]