pki: Fix ssh_pki_publickey_to_base64() warnings.
pki: Fix ssh_pki_publickey_to_base64() warnings.

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