separate TLSFlags TLSVersion to standalone file or import bearssl when defined ssl
https://github.com/status-im/nim-chronos/blob/67f0f1224fe8176cf66c3fc35c74e313906d9658/chronos/streams/tlsstream.nim#L12

`TLSVersion` `TLSFlags`

my proc has params accept TLSVersion TLSFlags also has isSecurity flag, so ssl and non-ssl share same body, I dont want compile bearssl when not defined ssl.