Fix the TCH/H decoder and demapper XML definitions

- The second argument of tch_h_decoder constructor is a string that
  accepts the value of MultiRate configuration element and not an enum
  like the tch_f_decoder decoder.
- Make the demapper's burst sink required.
- Make all parameters visible.
- Rename the TCH/H Channel parameter to Sub-channel number.
- Add the qa_tch_h_decoder test in the CMakeLists.txt
- Fix several typos

Change-Id: I92d4f49955c634df7d76f17cfb58d7106846c1bd
diff --git a/apps/grgsm_decode b/apps/grgsm_decode
index 3bc0db3..4bd1d95 100755
--- a/apps/grgsm_decode
+++ b/apps/grgsm_decode
@@ -344,7 +344,7 @@
     tch_options.add_option("--sub-channel", dest="tch_h_channel", default="0", type='intx',
                            help="TCH/H sub-channel. [default=0]")
     tch_options.add_option("--multi-rate", dest="multi_rate", default="", type='string',
-                           help="The MultiRrate configuration element from the Assignment Command message. "
+                           help="The MultiRate configuration element from the Assignment Command message. "
                            "Example: 28111a40. See 3GPP TS 44.018 - 10.5.2.21aa MultiRate configuration")
     tch_options.add_option("--voice-boundary", dest="enable_voice_boundary_detection", action="store_true", default=False,
                            help="Enable voice boundary detection for traffic channels. This can help reduce noice in the output.")