cve/cve-2017-16939: Add kernel commit

Add kernel commit hash that fixes the issue into the top level comment.

Signed-off-by: Cyril Hrubis <[email protected]>

Author: metan-ucw

testcases/cve/cve-2017-16939.c

@@ -14,8 +14,10 @@
  * You should have received a copy of the GNU General Public License
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  */
-/* Regression test for CVE-2017-16939
- * based on the reproducing code from Mohammed Ghannam, published on
+/* Regression test for commit:
+ * 1137b5e2529a ipsec: Fix aborted xfrm policy dump crash aka CVE-2017-16939
+ *
+ * Based on the reproducing code from Mohammed Ghannam, published on
  * https://blogs.securiteam.com/index.php/archives/3535
  *
  * CAUTION! If your system is vulnerable to this CVE, the kernel