Added check to qtemporaryfile unittest if run as root user

- nonWritableCurrentDir() function not valid test if run as root
  so added skip.

Change-Id: I772e8356e6f798f5acdf7688c55f3241ad012a43
Reviewed-by: Kurt Korbatits  <kurt.korbatits@nokia.com>
Reviewed-by: Rohan McGovern <rohan.mcgovern@nokia.com>
Reviewed-by: Jason McDonald <jason.mcdonald@nokia.com>

tests/auto/corelib/io/qtemporaryfile/tst_qtemporaryfile.cpp

@@ -256,6 +256,9 @@ void tst_QTemporaryFile::autoRemove()
 void tst_QTemporaryFile::nonWritableCurrentDir()
 {
 #ifdef Q_OS_UNIX
+    if (::geteuid() == 0)
+        QSKIP("not valid running this test as root");
+
     struct ChdirOnReturn
     {
         ChdirOnReturn(const QString& d) : dir(d) {}