media: vpx3220: make array input_vals static, makes object smaller

Don't populate the array input_vals on the stack but instead make it
static. Makes the object code smaller by 106 bytes.

Before:
   text	   data	    bss	    dec	    hex	filename
  11744	   3536	    128	  15408	   3c30	drivers/media/i2c/vpx3220.o

After:
   text	   data	    bss	    dec	    hex	filename
  11574	   3600	    128	  15302	   3bc6	drivers/media/i2c/vpx3220.o

(gcc version 9.2.1, amd64)

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>