watchdog: w83627hf: make const array chip_name static

Don't populate array chip_name on the stack but instead make it static.
Makes the object code smaller by 40 bytes:

Before:
   text	   data	    bss	    dec	    hex	filename
   5641	   2840	    384	   8865	   22a1	drivers/watchdog/w83627hf_wdt.o

After:
   text	   data	    bss	    dec	    hex	filename
   5545	   2896	    384	   8825	   2279	drivers/watchdog/w83627hf_wdt.o

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>