Update libssh2.h to the latest version
Update libssh2.h to the latest version

AriX/NMSSH,eugenehp/NMSSH,ricobeck/NMSSH,endSly/NMSSH,clemensg/NMSSH,gnachman/NMSSH,eugenehp/NMSSH,doo/NMSSH,Lejdborg/NMSSH,mralexgray/NMSSH,3drobotics/NMSSH,tbartelmess/NMSSH,gnachman/NMSSH,3drobotics/NMSSH,tbartelmess/NMSSH,clemensg/NMSSH,Lakhman/NMSSH,Lejdborg/NMSSH,AriX/NMSSH,gnachman/NMSSH,doo/NMSSH,NMSSH/NMSSH,ADGrant/NMSSH,doo/NMSSH,eugenehp/NMSSH,mralexgray/NMSSH,Lakhman/NMSSH,ricobeck/NMSSH,mralexgray/NMSSH,tbartelmess/NMSSH,eugenehp/NMSSH,gnachman/NMSSH,Lejdborg/NMSSH,3drobotics/NMSSH,ADGrant/NMSSH,clemensg/NMSSH,endSly/NMSSH,Lakhman/NMSSH,NMSSH/NMSSH,endSly/NMSSH,AriX/NMSSH,doo/NMSSH,mralexgray/NMSSH,Lakhman/NMSSH,AriX/NMSSH,ricobeck/NMSSH,NMSSH/NMSSH,clemensg/NMSSH,ADGrant/NMSSH,Lejdborg/NMSSH,tbartelmess/NMSSH