Upgrade and cleanup cppcheck suppressions to version 1.76.1

Also renamed the suppressions file to the standard name.

refs #831

src/blackmisc/datacache.cpp

@@ -332,6 +332,7 @@ namespace BlackMisc
     class BLACKMISC_EXPORT CDataCacheRevision::Session
     {
     public:
+        // cppcheck-suppress unusedFunction
         Session(const QString &filename) : m_filename(filename) {}
         void updateSession();
         const QUuid &uuid() const { return m_uuid; }

src/blackmisc/stacktrace.cpp

@@ -118,6 +118,7 @@ namespace BlackMisc
         return result;
     }
 #else
+    // cppcheck-suppress unusedFunction
     QStringList getStackTrace()
     {
         return { "No stack trace on this platform" };

src/blackmisc/verify.cpp

@@ -27,6 +27,7 @@ namespace BlackMisc
 {
     namespace Private
     {
+        // cppcheck-suppress unusedFunction
         void failedVerify(const char *condition, const char *filename, int line, const char *context, const char *message)
         {
             Q_UNUSED(condition);