Updated irssi packages fix security vulnerabilities

While waiting for the channel synchronization, Irssi may incorrectly fail to remove destroyed channels from the query list, resulting in use after free conditions when updating the state later on (CVE-2017-15227). When installing themes with unterminated color formatting sequences, Irssi may access data beyond the end of the string. (CVE-2017-15228). Certain incorrectly formatted DCC CTCP messages could cause NULL pointer dereference (CVE-2017-15721). In certain cases Irssi may fail to verify that a Safe channel ID is long enough, causing reads beyond the end of the string (CVE-2017-15722). Overlong nicks or targets may result in a NULL pointer dereference while splitting the message (CVE-2017-15723).