Merge pull request #8575 from ColtonWilley/fix_cryptocb_rsa_pad_ret_len

Fix outlen return for RSA private decrypt with WOLF_CRYPTO_CB_RSA_PAD

wolfcrypt/src/rsa.c

@@ -3603,6 +3603,9 @@ static int RsaPrivateDecryptEx(const byte* in, word32 inLen, byte* out,
         ret = wc_CryptoCb_RsaPad(in, inLen, out,
                             &outLen, rsa_type, key, rng, &padding);
         if (ret != WC_NO_ERR_TRACE(CRYPTOCB_UNAVAILABLE)) {
+            if (ret == 0) {
+                ret = (int)outLen;
+            }
             break;
         }
     }