ssl: fix max sequence number so it does not overflow

The old value of 18446744073709552000 was calculated using math:pow
which returns float therefore isn't precise. And it would overflow:

erlang:integer_to_list(18446744073709552000, 16) = "10000000000000180"

This patch changes MAX_SEQENCE_NUMBER to value calculated with bitwise
shift:
(1 bsl 64) - 1 = 18446744073709551615