CID 1508992: Uninitialized scalar variable

[maskit]

441  if (ts_lua_hex_to_bin(key_bin, key, klen) == NULL) {
442    TSfree(key_bin);
443    return luaL_error(L, "hex to binary conversion failed");
444  }
445  key_bin_len = klen / 2;
446
447  HMAC(EVP_sha256(), key_bin, key_bin_len, src, slen, sha_buf, &output_length);
448
   	
CID 1508992 (#1 of 1): Uninitialized scalar variable (UNINIT)
9. uninit_use_in_call: Using uninitialized element of array sha_buf when calling ts_lua_hex_dump. [[show details](https://scan6.scan.coverity.com/eventId=34625582-13&modelId=34625582-0&fileInstanceId=162996654&filePath=%2Fplugins%2Flua%2Fts_lua_string.c&fileStart=23&fileEnd=33)]
449  ts_lua_hex_dump(hex_buf, sha_buf, sizeof(sha_buf));
450  lua_pushlstring(L, (char *)hex_buf, sizeof(hex_buf));
451
452  TSfree(key_bin);
453  return 1;
454}