[shells/lshell] patches to update to upstream 0.9.18

[Damien Fleuriot]

Hello list,



Just submitted a PR to update shells/lshell to upstream's 0.9.18 :
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=215989

The update should close the shell escape vulnerability in 0.9.16_2 :
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=215988


Seeking peer review for the provided patches.


Cheers :)

Kindly do preserve the CC'd address, not sure I've subbed to ports@ ;)