bitbake: bitbake-selftest: utilize unittest.main better

This simplifies the script, and, gives new features. It is now possible
to run single test functions, for example. This is nice when writing new
test cases.

(Bitbake rev: 8c513580b9406b031674f799117eae7410f8e01c)

Signed-off-by: Markus Lehtonen <markus.lehtonen@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/bin/bitbake-selftest

@@ -25,31 +25,17 @@ try:
 except RuntimeError as exc:
     sys.exit(str(exc))
 
-def usage():
-    print('usage: [BB_SKIP_NETTESTS=yes] %s [-v] [testname1 [testname2]...]' % os.path.basename(sys.argv[0]))
-
-verbosity = 1
-
-tests = sys.argv[1:]
-if '-v' in sys.argv:
-    tests.remove('-v')
-    verbosity = 2
-
-if tests:
-    if '--help' in sys.argv[1:]:
-        usage()
-        sys.exit(0)
-else:
-    tests = ["bb.tests.codeparser",
-             "bb.tests.cow",
-             "bb.tests.data",
-             "bb.tests.fetch",
-             "bb.tests.parse",
-             "bb.tests.utils"]
+tests = ["bb.tests.codeparser",
+         "bb.tests.cow",
+         "bb.tests.data",
+         "bb.tests.fetch",
+         "bb.tests.parse",
+         "bb.tests.utils"]
 
 for t in tests:
     t = '.'.join(t.split('.')[:3])
     __import__(t)
 
-unittest.main(argv=["bitbake-selftest"] + tests, verbosity=verbosity)
 
+if __name__ == '__main__':
+        unittest.main(defaultTest=tests)