IPTVChannelInfo: explictly set IPTVTuningData protocol to invalid

... and avoid the protocol probe. The uses in the channel fetching code do not
require it and this avoids hitting every single URL during a channel scan
(which some providers do not appreciate).

The channel fetcher code doesn't need the protocol, since it calls none of the
relevant methods.

Since the IPTVTuningData contructor argument list has changed we know that
there are no other users of that particular form.

While there constify `IsHLSPlaylist`

Refs #13488
Signed-off-by: Paul Harrison <pharrison@mythtv.org>
(cherry picked from commit 896f0c8)

mythtv/libs/libmythtv/channelscan/iptvchannelfetcher.h

@@ -39,15 +39,11 @@ class IPTVChannelInfo
                     uint programnumber) :
         m_name(name), m_xmltvid(xmltvid), m_programNumber(programnumber),
         m_tuning(data_url, data_bitrate,
-                 fec_type, fec_url0, fec_bitrate0, fec_url1, fec_bitrate1)
+                 fec_type, fec_url0, fec_bitrate0, fec_url1, fec_bitrate1,
+                 IPTVTuningData::inValid)
     {
     }
 
-    bool IsValid(void) const
-    {
-        return !m_name.isEmpty() && m_tuning.IsValid();
-    }
-
   public:
     QString        m_name;
     QString        m_xmltvid;

mythtv/libs/libmythtv/iptvtuningdata.h

@@ -71,11 +71,12 @@ class MTV_PUBLIC IPTVTuningData
     IPTVTuningData(const QString &data_url, uint data_bitrate,
                    const QString &fec_type,
                    const QString &fec_url0, uint fec_bitrate0,
-                   const QString &fec_url1, uint fec_bitrate1) :
+                   const QString &fec_url1, uint fec_bitrate1,
+                   const IPTVProtocol protocol) :
         m_data_url(data_url),
-        m_fec_type(kNone), m_fec_url0(fec_url0), m_fec_url1(fec_url1)
+        m_fec_type(kNone), m_fec_url0(fec_url0), m_fec_url1(fec_url1),
+        m_protocol(protocol)
     {
-        GuessProtocol();
         m_bitrate[0] = data_bitrate;
         m_bitrate[1] = fec_bitrate0;
         m_bitrate[2] = fec_bitrate1;
@@ -218,7 +219,7 @@ class MTV_PUBLIC IPTVTuningData
     }
 
   protected:
-    bool IsHLSPlaylist(void)
+    bool IsHLSPlaylist(void) const
     {
         if (!qApp)
         {