misc: Don't leak memory on ssh_path_expand_escape() on error.
misc: Don't leak memory on ssh_path_expand_escape() on error.

(cherry picked from commit 61d032fc03e0055c859931f466bc75fbdf36385a)

mwgoldsmith/ssh,mwgoldsmith/ssh,mwgoldsmith/ssh,mwgoldsmith/ssh,mwgoldsmith/libssh,mwgoldsmith/libssh,mwgoldsmith/libssh,mwgoldsmith/libssh