travis: Run a gcrypt test with leak-detective

And also enable gcrypt in the all tests with leak-detective enabled.

.travis.yml

@@ -25,8 +25,8 @@ env:
     - TEST=default LEAK_DETECTIVE=yes
     - TEST=openssl
     - TEST=openssl LEAK_DETECTIVE=yes
-    # libgcrypt can't be deinitialized so we can't test it with leak detective
     - TEST=gcrypt
+    - TEST=gcrypt LEAK_DETECTIVE=yes
     # we can't test Vstr as negative int args are not properly passed to CBs
     - TEST=printf-builtin
     - TEST=printf-builtin LEAK_DETECTIVE=yes