MINOR: ssl: set ssl-min-ver in ambiguous configurations

Using ssl-max-ver without ssl-min-ver is ambiguous.

When the ssl-min-ver is not configured, and ssl-max-ver is set to a
value lower than the default ssl-min-ver (which is TLSv1.2 currently),
set the ssl-min-ver to the value of ssl-max-ver, and emit a warning.
2 files changed