Fix build with -trace lttng

Fix superfluous space in qtgui.tracepoints and make tracegen more
lenient towards unknown types (the ETW implementation outright ignores
those).

Pick-to: 5.15
Fixes: QTBUG-86546
Change-Id: I71cc323afa1009dbaefe20e55818ecb6c0b09c59
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>
Reviewed-by: Milian Wolff <milian.wolff@kdab.com>

src/tools/tracegen/lttng.cpp

@@ -98,7 +98,8 @@ static void writeCtfMacro(QTextStream &stream, const Tracepoint::Field &field)
                << "ctf_integer(int, height, " << name << ".height()) ";
         return;
     case Tracepoint::Field::Unknown:
-        panic("Cannot deduce CTF type for '%s %s", qPrintable(paramType), qPrintable(name));
+        justified_worry("Cannot deduce CTF type for '%s %s'", qPrintable(paramType),
+                        qPrintable(name));
         break;
     }
 }

src/tools/tracegen/panic.cpp

@@ -57,3 +57,16 @@ void panic(const char *fmt, ...)
 
     exit(EXIT_FAILURE);
 }
+
+void justified_worry(const char *fmt, ...)
+{
+    va_list ap;
+
+    fprintf(stderr, "tracegen: warning: ");
+
+    va_start(ap, fmt);
+    vfprintf(stderr, fmt, ap);
+    va_end(ap);
+
+    fputc('\n', stderr);
+}

src/tools/tracegen/panic.h

@@ -41,5 +41,6 @@
 #define PANIC_H
 
 void panic(const char *fmt, ...);
+void justified_worry(const char *fmt, ...);
 
 #endif // PANIC_H