Use negated option for controlling TLS support.
A positive option looks better, but comes with the following compatibility
issue: people using a custom config.h that is not based on the default
config.h and need TLS support would need to manually change their config in
order to still get TLS.
Work around that by making the public option negative. Internally the positive
option is used, though.
In the future (when preparing the next major version), we might want to switch
back to a positive option as this would be more consistent with other options
we have.
diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index 653f857..1a4eaf6 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -1337,8 +1337,8 @@
/**
* \brief Set the transport type (TLS or DTLS).
- * Default: TLS if #MBEDTLS_SSL_PROTO_TLS is defined, else
- * DTLS.
+ * Default: TLS unless #MBEDTLS_SSL_PROTO_NO_TLS is defined,
+ * else DTLS.
*
* \note For DTLS, you must either provide a recv callback that
* doesn't block, or one that handles timeouts, see