tls: clean conninfo before filling new data
tls: clean conninfo before filling new data

It can lead to memleak if tls_handshake called after
it returns 0.  It's probably caller bug, but the
conninfo filling uses rather fragile coding style,
so it seems like good precaution.

ifduyue/libusual,markokr/libusual,markokr/libusual,ifduyue/libusual,ifduyue/libusual,ifduyue/libusual,markokr/libusual,markokr/libusual