channelutil.cpp: fix channel count if visible is 'Always Visible'

As each channel was counted, the value was incremented by the contents of
the visible field, which is OK for kChannelVisible (1). But when marked
kChannelAlwaysVisible (2), the count was bumped by two causing the following
warning log entry:

    ... Found multiple visible channels for <some name>, using chanid <some id>

mythtv/libs/libmythtv/channelutil.cpp

@@ -1960,11 +1960,13 @@ bool ChannelUtil::GetChannelData(
                         : query.value(8).toInt();
         chanid        = query.value(9).toUInt();
 
-        found += query.value(10).toInt();
+        if (query.value(10).toInt() > kChannelNotVisible)
+            found++;
     }
 
     while (query.next())
-        found += query.value(10).toInt();
+        if (query.value(10).toInt() > kChannelNotVisible)
+            found++;
 
     if (found == 0 && chanid)
     {