media: staging: rkisp1: rsz: make const array static, makes object smaller

Don't populate the const array dev_names on the stack but instead it
static. Makes the object code smaller by 15 bytes.

Before:
   text	   data	    bss	    dec	    hex	filename
  17091	   2648	     64	  19803	   4d5b	media/rkisp1/rkisp1-resizer.o

After:
   text	   data	    bss	    dec	    hex	filename
  17012	   2712	     64	  19788	   4d4c	media/rkisp1/rkisp1-resizer.o

(gcc version 10.2.0)

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+huawei@kernel.org>