hw/display/cg3.c: Fix memory leak

Signed-off-by: NShannon Zhao <zhaoshenglong@huawei.com>
Signed-off-by: NShannon Zhao <shannon.zhao@linaro.org>
Signed-off-by: NMichael Tokarev <mjt@tls.msk.ru>

hw/display/cg3.c

@@ -303,6 +303,7 @@ static void cg3_realizefn(DeviceState *dev, Error **errp)
     if (fcode_filename) {
         ret = load_image_targphys(fcode_filename, s->prom_addr,
                                   FCODE_MAX_ROM_SIZE);
+        g_free(fcode_filename);
         if (ret < 0 || ret > FCODE_MAX_ROM_SIZE) {
             error_report("cg3: could not load prom '%s'", CG3_ROM_FILE);
         }