hw/display/tcx.c: Fix memory leak

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

hw/display/tcx.c

@@ -1018,6 +1018,7 @@ static void tcx_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("tcx: could not load prom '%s'", TCX_ROM_FILE);
         }