migration: fix memory leak in qmp_migrate_set_parameters

"tmp.tls_hostname" and "tmp.tls_creds" allocated by migrate_params_test_apply()
is forgot to free at the end of qmp_migrate_set_parameters(). Fix that.

The leak stack:
Direct leak of 2 byte(s) in 2 object(s) allocated from:
   #0 0xffffb597c20b in __interceptor_malloc (/usr/lib64/libasan.so.4+0xd320b)
   #1 0xffffb52dcb1b in g_malloc (/usr/lib64/libglib-2.0.so.0+0x58b1b)
   #2 0xffffb52f8143 in g_strdup (/usr/lib64/libglib-2.0.so.0+0x74143)
   #3 0xaaaac52447fb in migrate_params_test_apply (/usr/src/debug/qemu-4.1.0/migration/migration.c:1377)
   #4 0xaaaac52fdca7 in qmp_migrate_set_parameters (/usr/src/debug/qemu-4.1.0/qapi/qapi-commands-migration.c:192)
   #5 0xaaaac551d543 in qmp_dispatch (/usr/src/debug/qemu-4.1.0/qapi/qmp-dispatch.c:165)
   #6 0xaaaac52a0a8f in qmp_dispatch (/usr/src/debug/qemu-4.1.0/monitor/qmp.c:125)
   #7 0xaaaac52a1c7f in monitor_qmp_dispatch (/usr/src/debug/qemu-4.1.0/monitor/qmp.c:214)
   #8 0xaaaac55cb0cf in aio_bh_call (/usr/src/debug/qemu-4.1.0/util/async.c:117)
   #9 0xaaaac55d4543 in aio_bh_poll (/usr/src/debug/qemu-4.1.0/util/aio-posix.c:459)
   #10 0xaaaac55cae0f in aio_dispatch (/usr/src/debug/qemu-4.1.0/util/async.c:268)
   #11 0xffffb52d6a7b in g_main_context_dispatch (/usr/lib64/libglib-2.0.so.0+0x52a7b)
   #12 0xaaaac55d1e3b(/usr/bin/qemu-kvm-4.1.0+0x1622e3b)
   #13 0xaaaac4e314bb(/usr/bin/qemu-kvm-4.1.0+0xe824bb)
   #14 0xaaaac47f45ef(/usr/bin/qemu-kvm-4.1.0+0x8455ef)
   #15 0xffffb4bfef3f in __libc_start_main (/usr/lib64/libc.so.6+0x23f3f)
   #16 0xaaaac47ffacb(/usr/bin/qemu-kvm-4.1.0+0x850acb)

Direct leak of 2 byte(s) in 2 object(s) allocated from:
   #0 0xffffb597c20b in __interceptor_malloc (/usr/lib64/libasan.so.4+0xd320b)
   #1 0xffffb52dcb1b in g_malloc (/usr/lib64/libglib-2.0.so.0+0x58b1b)
   #2 0xffffb52f8143 in g_strdup (/usr/lib64/libglib-2.0.so.0+0x74143)
   #3 0xaaaac5244893 in migrate_params_test_apply (/usr/src/debug/qemu-4.1.0/migration/migration.c:1382)
   #4 0xaaaac52fdca7 in qmp_migrate_set_parameters (/usr/src/debug/qemu-4.1.0/qapi/qapi-commands-migration.c:192)
   #5 0xaaaac551d543 in qmp_dispatch (/usr/src/debug/qemu-4.1.0/qapi/qmp-dispatch.c)
   #6 0xaaaac52a0a8f in qmp_dispatch (/usr/src/debug/qemu-4.1.0/monitor/qmp.c:125)
   #7 0xaaaac52a1c7f in monitor_qmp_dispatch (/usr/src/debug/qemu-4.1.0/monitor/qmp.c:214)
   #8 0xaaaac55cb0cf in aio_bh_call (/usr/src/debug/qemu-4.1.0/util/async.c:117)
   #9 0xaaaac55d4543 in aio_bh_poll (/usr/src/debug/qemu-4.1.0/util/aio-posix.c:459)
   #10 0xaaaac55cae0f in in aio_dispatch (/usr/src/debug/qemu-4.1.0/util/async.c:268)
   #11 0xffffb52d6a7b in g_main_context_dispatch (/usr/lib64/libglib-2.0.so.0+0x52a7b)
   #12 0xaaaac55d1e3b(/usr/bin/qemu-kvm-4.1.0+0x1622e3b)
   #13 0xaaaac4e314bb(/usr/bin/qemu-kvm-4.1.0+0xe824bb)
   #14 0xaaaac47f45ef (/usr/bin/qemu-kvm-4.1.0+0x8455ef)
   #15 0xffffb4bfef3f in __libc_start_main (/usr/lib64/libc.so.6+0x23f3f)
   #16 0xaaaac47ffacb(/usr/bin/qemu-kvm-4.1.0+0x850acb)

Signed-off-by: Chuan Zheng <[email protected]>
Reviewed-by: KeQian Zhu <[email protected]>
Reviewed-by: HaiLiang <[email protected]>
Reviewed-by: Juan Quintela <[email protected]>
Signed-off-by: Juan Quintela <[email protected]>

migration/migration.c

@@ -1343,12 +1343,12 @@ static void migrate_params_test_apply(MigrateSetParameters *params,
 
     if (params->has_tls_creds) {
         assert(params->tls_creds->type == QTYPE_QSTRING);
-        dest->tls_creds = g_strdup(params->tls_creds->u.s);
+        dest->tls_creds = params->tls_creds->u.s;
     }
 
     if (params->has_tls_hostname) {
         assert(params->tls_hostname->type == QTYPE_QSTRING);
-        dest->tls_hostname = g_strdup(params->tls_hostname->u.s);
+        dest->tls_hostname = params->tls_hostname->u.s;
     }
 
     if (params->has_max_bandwidth) {