Fix DoUserAuthBanner()

Author: yosuke-wolfssl

src/internal.c

@@ -8514,7 +8514,7 @@ static int DoUserAuthBanner(WOLFSSH* ssh, byte* buf, word32 len, word32* idx)
         ret = GetString(banner, &bannerSz, buf, len, idx);
 
     if (ret == WS_SUCCESS)
-        ret = GetSize(&bannerSz, buf, len, idx);
+        ret = GetSkip(buf, len, idx);
 
     if (ret == WS_SUCCESS) {
         if (ssh->ctx->showBanner) {