channels: Set errors on return.
channels: Set errors on return.

Signed-off-by: Andreas Schneider <5be00ddc76278cf6077f5047ca3384a88460c671@cryptomilk.org>
(cherry picked from commit 7ae59c571afae0bae1f54a4d8b16a456b6469535)

miloj/libssh-v0.5,mwgoldsmith/libssh,mwgoldsmith/ssh,mwgoldsmith/ssh,mwgoldsmith/ssh,mwgoldsmith/libssh,mwgoldsmith/ssh,miloj/libssh-v0.5,mwgoldsmith/libssh,mwgoldsmith/libssh,miloj/libssh-v0.5,miloj/libssh-v0.5