tests: fix qmp-test leak

Direct leak of 913 byte(s) in 43 object(s) allocated from:
    #0 0x55880a15df60 in __interceptor_malloc (/home/elmarco/src/qq/build/tests/qmp-test+0x110f60)
    #1 0x7f3f20fd098f in _IO_vasprintf (/lib64/libc.so.6+0x8098f)

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20180104160523.22995-15-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

tests/qmp-test.c

@@ -271,7 +271,7 @@ static void add_query_tests(QmpSchema *schema)
 {
     SchemaInfoList *tail;
     SchemaInfo *si, *arg_type, *ret_type;
-    const char *test_name;
+    char *test_name;
 
     /* Test the query-like commands */
     for (tail = schema->list; tail; tail = tail->next) {
@@ -297,6 +297,7 @@ static void add_query_tests(QmpSchema *schema)
 
         test_name = g_strdup_printf("qmp/%s", si->name);
         qtest_add_data_func(test_name, si->name, test_query);
+        g_free(test_name);
     }
 }