Branch HEAD

b=15191
i=wangdi, shadow

during liblustre test during

mgc_llog_init() (lustre/mgc/libmgc.c)
  llog_initiator_connect(ctxt)

while in liblustre lib, it is defined as an empty function only return 0, while
in kernel lib, it set the context's loc_imp. And this context's loc_imp is
required after in llog_client_create().

This fix defines llog_initiator_connect() in both lib (kernel version and
liblustre version)