selftest/runtime-test.py: Add test for import test from other layers

There are some features in testimage/testexport that are not tested;
this might lead to break some of these features without notice.

This adds a new test in order to test two features of testimage:
  - Import test from other layers.
  - Install/Unistall in the DUT without a package manager.

[YOCTO #9764]
[YOCTO #9766]

(From OE-Core rev: cffab2257dacfa741c64611dfdf361f77aff9460)

Signed-off-by: Mariano Lopez <mariano.lopez@linux.intel.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta-selftest/lib/oeqa/runtime/selftest.json

@@ -0,0 +1,6 @@
+{
+    "test_install_package": {
+        "pkg": "socat",
+        "rm": true
+    }
+}

meta-selftest/lib/oeqa/runtime/selftest.py

@@ -0,0 +1,31 @@
+from oeqa.oetest import oeRuntimeTest, skipModule
+from oeqa.utils.decorators import *
+
+class Selftest(oeRuntimeTest):
+
+    @skipUnlessPassed("test_ssh")
+    def test_install_package(self):
+        """
+        Summary: Check basic package installation functionality.
+        Expected: 1. Before the test socat must be installed using scp.
+                  2. After the test socat must be unistalled using ssh.
+                     This can't be checked in this test.
+        Product: oe-core
+        Author: Mariano Lopez <mariano.lopez@intel.com>
+        """
+
+        (status, output) = self.target.run("socat -V")
+        self.assertEqual(status, 0, msg="socat is not installed")
+
+    @skipUnlessPassed("test_install_package")
+    def test_verify_unistall(self):
+        """
+        Summary: Check basic package installation functionality.
+        Expected: 1. test_install_package must unistall socat.
+                     This test is just to verify that.
+        Product: oe-core
+        Author: Mariano Lopez <mariano.lopez@intel.com>
+        """
+
+        (status, output) = self.target.run("socat -V")
+        self.assertNotEqual(status, 0, msg="socat is still installed")