net: llc: Correct some function names in header

Fix the following make W=1 kernel build warning:

 net/llc/llc_c_ev.c:622: warning: expecting prototype for conn_ev_qlfy_last_frame_eq_1(). Prototype was for llc_conn_ev_qlfy_last_frame_eq_1() instead
 net/llc/llc_c_ev.c:636: warning: expecting prototype for conn_ev_qlfy_last_frame_eq_0(). Prototype was for llc_conn_ev_qlfy_last_frame_eq_0() instead

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>