Fix typo in doxy docs for ssl_pkcs11_sign()
diff --git a/include/mbedtls/pkcs11.h b/include/mbedtls/pkcs11.h
index 6cfe5a9..cf8d8c4 100644
--- a/include/mbedtls/pkcs11.h
+++ b/include/mbedtls/pkcs11.h
@@ -206,7 +206,7 @@
  * \return         A non-zero error code on failure.
  *
  * \note           The \p sig buffer must be as large as the size of
- *                 <code>ctx->N<code>. For example, 128 bytes if RSA-1024 is
+ *                 <code>ctx->N</code>. For example, 128 bytes if RSA-1024 is
  *                 used.
  */
 MBEDTLS_DEPRECATED static inline int mbedtls_ssl_pkcs11_sign( void *ctx,