Fixed typo in ssl.h
diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index 42c9779..495e02c 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -2436,7 +2436,7 @@
  * \param len      how many bytes must be written
  *
  * \return         the number of bytes actually written (may be less than len),
- *                 or MBEDTLS_ERR_SSL_WANT_WRITE of MBEDTLS_ERR_SSL_WANT_READ,
+ *                 or MBEDTLS_ERR_SSL_WANT_WRITE or MBEDTLS_ERR_SSL_WANT_READ,
  *                 or another negative error code.
  *
  * \note           If this function returns something other than a positive