ptr_leak

Description: MaraDNS would leak memory when making a recursive query for
             a PTR record that is a CNAME that doesn't point to an existing
             record.

Expected output of test: MaraDNS does not leak memory

Presence of bug output: MaraDNS leaks memory

When fixed: 1.2.12.01

Note: Valgrind needed to run this test; Valgrind may report 
      "68 bytes possibly lost" even though memory is not really leaking

