llc: Make llc_conn_ev_qfyr_t function pointer arrays const

It's better when function pointer arrays aren't modifiable.

Net change from original:

$ size net/llc/built-in.o.*
   text	   data	    bss	    dec	    hex	filename
  61065	  12886	   1344	  75295	  1261f	net/llc/built-in.o.new
  47113	  27030	   1344	  75487	  126df	net/llc/built-in.o.old

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --cc include/net/llc_c_st.h
Simple merge

diff --cc net/llc/llc_c_st.c
Simple merge

diff --cc net/llc/llc_conn.c
Simple merge