troubleshooter: deferred message for fatal errors (#491)

## Description of change
When the game logs a fatal error message, queue up a deferred message
for the troubleshooter.

src/spice2x/util/deferlog.cpp

@@ -32,6 +32,16 @@ namespace deferredlogs {
         deferred_errors.emplace_back(messages);
     }
 
+    void report_fatal_message() {
+        static std::once_flag printed;
+        std::call_once(printed, []() {
+            deferredlogs::defer_error_messages({
+                "game reported FATAL error(s)",
+                "    look for messages containing F: in the log",
+                });
+        });
+    }
+
     void dump_to_logger(bool is_crash) {
         static std::once_flag printed;
         std::call_once(printed, [is_crash]() {

src/spice2x/util/deferlog.h

@@ -10,6 +10,7 @@ namespace deferredlogs {
     extern const std::initializer_list<std::string> SUPERSTEP_SOUND_ERROR_MESSAGE;
 
     void set_softid(const std::string& softid);
+    void report_fatal_message();
     void defer_error_messages(std::initializer_list<std::string> messages);
     void dump_to_logger(bool is_crash=false);
 }