mlogc: Changes the default SSL algo to TLS 1.2

As reported by Josh Amishav-Zlatin, mlogc was making usage of SSLv3 instead of
TLS 1.2. Servers should not answer SSLv3 after poodle.
mlogc: Checks if CURL_SSLVERSION_TLSv1_2 is defined before use it

Seems like libcurl versions bellow to v7.34.0 does not support
`CURL_SSLVERSION_TLSv1_2'. If `CURL_SSLVERSION_TLSv1_2' is not defined using
CURL_SSLVERSION_TLSv1 instead.