Don't populate the arrays port_map and sl_map on the stack but
instead make them static. Makes the object code smaller by 64 bytes.

Before:
   text	   data	    bss	    dec	    hex	filename
  49575	   6872	     64	  56511	   dcbf	hisilicon/hns/hns_dsaf_main.o

After:
   text	   data	    bss	    dec	    hex	filename
  49350	   7032	     64	  56446	   dc7e	hisilicon/hns/hns_dsaf_main.o

(gcc version 9.2.1, amd64)
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>