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/grc/demapping/gsm_tch_h_chans_demapper.xml b/grc/demapping/gsm_tch_h_chans_demapper.xml
index f2bd67f..52148f5 100644
--- a/grc/demapping/gsm_tch_h_chans_demapper.xml
+++ b/grc/demapping/gsm_tch_h_chans_demapper.xml
@@ -10,22 +10,29 @@
     <key>timeslot_nr</key>
     <value>2</value>
     <type>int</type>
-    <hide>part</hide>
+    <hide>none</hide>
   </param>
 
   <param>
-    <name>TCH/H Channel</name>
+    <name>Sub-channel number</name>
     <key>tch_h_channel</key>
     <value>0</value>
     <type>int</type>
-    <hide>#if $tch_type() == 0 then 'all' else 'none'#</hide>
+    <hide>none</hide>
+    <option>
+      <name>0</name>
+      <key>0</key>
+    </option>
+    <option>
+      <name>1</name>
+      <key>1</key>
+    </option>
   </param>
   <check>$tch_h_channel() &gt; -1 and $tch_h_channel() &lt; 2</check>
 
   <sink>
     <name>bursts</name>
     <type>message</type>
-    <optional>1</optional>
   </sink>
   <source>
     <name>tch_bursts</name>