libxl: fix leak of corename in handle_domain_death

Coverity-ID: 1087192
Signed-off-by: Matthew Daley <mattjd@gmail.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>

tools/libxl/xl_cmdimpl.c

@@ -1621,6 +1621,7 @@ static int handle_domain_death(uint32_t *r_domid,
             LOG("dumping core to %s", corefile);
             rc=libxl_domain_core_dump(ctx, *r_domid, corefile, NULL);
             if (rc) LOG("core dump failed (rc=%d).", rc);
+            free(corefile);
         }
         /* No point crying over spilled milk, continue on failure. */