Add a delimiter before "TracerPid"

Future-proofing against a future version of the Linux kernel adding a
"FooTracerPid:" before the TracerPid entry.

Change-Id: I42e7ef1a481840699a8dffff140347457902900f
Reviewed-by: Simon Hausmann <simon.hausmann@theqtcompany.com>

src/testlib/qtestcase.cpp

@@ -2503,7 +2503,7 @@ static bool debuggerPresent()
         return false;
     }
     buffer[size] = 0;
-    const char tracerPidToken[] = "TracerPid:";
+    const char tracerPidToken[] = "\nTracerPid:";
     char *tracerPid = strstr(buffer, tracerPidToken);
     if (!tracerPid) {
         close(fd);