misc: Use strncpy instead of strcat.
misc: Use strncpy instead of strcat.

This is just hardening the code.

Found by Coverity.

nviennot/libssh,jt1/honeypot-libssh,sebadoom/libssh,taikoo/libssh,Distrotech/libssh,nviennot/libssh,mwgoldsmith/libssh,taikoo/libssh,Distrotech/libssh,kedazo/libssh,elastichosts/libssh,mwgoldsmith/libssh,robxu9/libssh,kedazo/libssh,mwgoldsmith/ssh,mwgoldsmith/libssh,wangshawn/libssh,DouglasHeriot/libssh,DouglasHeriot/libssh,robxu9/libssh,robxu9/libssh,Distrotech/libssh,bigcat26/libssh-mod,jt1/honeypot-libssh,pouete/libssh,elastichosts/libssh,elastichosts/libssh,taikoo/libssh,Distrotech/libssh,jt1/honeypot-libssh,kedazo/libssh,wangshawn/libssh,bigcat26/libssh-mod,bigcat26/libssh-mod,kedazo/libssh,sebadoom/libssh,pouete/libssh,jt1/honeypot-libssh,sebadoom/libssh,wangshawn/libssh,bigcat26/libssh-mod,taikoo/libssh,mwgoldsmith/ssh,nviennot/libssh,pouete/libssh,wangshawn/libssh,mwgoldsmith/ssh,DouglasHeriot/libssh,mwgoldsmith/ssh,mwgoldsmith/libssh,sebadoom/libssh,pouete/libssh,DouglasHeriot/libssh,nviennot/libssh,robxu9/libssh