ppc/spapr_nvdimm: use g_autofree in spapr_nvdimm_validate_opts()

Since we're using the string just once, just use g_autofree and
avoid leaking it without calling g_free().

Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20200825215749.213536-2-danielhb413@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

hw/ppc/spapr_nvdimm.c

@@ -33,7 +33,7 @@
 void spapr_nvdimm_validate_opts(NVDIMMDevice *nvdimm, uint64_t size,
                                 Error **errp)
 {
-    char *uuidstr = NULL;
+    g_autofree char *uuidstr = NULL;
     QemuUUID uuid;
     int ret;
 
@@ -54,7 +54,6 @@ void spapr_nvdimm_validate_opts(NVDIMMDevice *nvdimm, uint64_t size,
                                       &error_abort);
     ret = qemu_uuid_parse(uuidstr, &uuid);
     g_assert(!ret);
-    g_free(uuidstr);
 
     if (qemu_uuid_is_null(&uuid)) {
         error_setg(errp, "NVDIMM device requires the uuid to be set");