brcmsmac: make array addr static const, makes object smaller

Don't populate the array addr on the stack but instead it
static const. Makes the object code smaller by 79 bytes:

Before:
   text   data   bss     dec    hex filename
 176015  54652   128  230795  3858b .../broadcom/brcm80211/brcmsmac/main.o

After:
   text   data   bss     dec    hex filename
 175872  54716   128  230716  3853c .../broadcom/brcm80211/brcmsmac/main.o

(gcc version 10.3.0)

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210819125552.8888-1-colin.king@canonical.com