TWAI: Add ESP32-S2 support

This commit adds TWAI driver support for the
ESP32-S2. The following features were added:

- Expanded BRP support
- Expanded CLKOUT Divider Support
- Updated example READMEs

examples/peripherals/twai/twai_self_test/example_test.py

@@ -0,0 +1,23 @@
+# Need Python 3 string formatting functions
+from __future__ import print_function
+
+import ttfw_idf
+
+
+# TWAI Self Test Example constants
+STR_EXPECT = ("TWAI Self Test: Driver installed", "TWAI Self Test: Driver uninstalled")
+EXPECT_TIMEOUT = 20
+
+
+@ttfw_idf.idf_example_test(env_tag='Example_TWAI1')
+def test_twai_self_test_example(env, extra_data):
+    # Get device under test, flash and start example. "dut1" must be defined in EnvConfig
+    dut = env.get_dut('dut1', 'examples/peripherals/twai/twai_self_test', dut_class=ttfw_idf.ESP32DUT)
+    dut.start_app()
+
+    for string in STR_EXPECT:
+        dut.expect(string, timeout=EXPECT_TIMEOUT)
+
+
+if __name__ == '__main__':
+    test_twai_self_test_example()