oeqa/runtime: add test that the kernel has CONFIG_PREEMPT_RT enabled

This is the absolute bare minimum for testing the RT patches, but it
does mean we if we build and boot a RT kernel we can verify that it is
what we expect.

(From OE-Core rev: de7bd5b616b9af3a88d718c79e85a4b53efb3280)

Signed-off-by: Ross Burton <ross.burton@arm.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
(cherry picked from commit 0301d5845115d09299f87683b3efa46f3b4c7be9)
Signed-off-by: Steve Sakoman <steve@sakoman.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/lib/oeqa/runtime/cases/rt.py

@@ -0,0 +1,17 @@
+#
+# SPDX-License-Identifier: MIT
+#
+
+from oeqa.runtime.case import OERuntimeTestCase
+from oeqa.core.decorator.depends import OETestDepends
+
+class RtTest(OERuntimeTestCase):
+    @OETestDepends(['ssh.SSHTest.test_ssh'])
+    def test_is_rt(self):
+        """
+        Check that the kernel has CONFIG_PREEMPT_RT enabled.
+        """
+        status, output = self.target.run("uname -a")
+        self.assertEqual(status, 0, msg=output)
+        # Split so we don't get a substring false-positive
+        self.assertIn("PREEMPT_RT", output.split())