media: platform: sti: make a const arrays static, makes object smaller

Don't populate the const arrays on the stack but instead it
static. Makes the object code smaller by 8 bytes:

Before:
   text	   data	    bss	    dec	    hex	filename
  12504	   4568	      0	  17072	   42b0	media/platform/sti/hva/hva-h264.o

After:
   text	   data	    bss	    dec	    hex	filename
  12272	   4792	      0	  17064	   42a8	media/platform/sti/hva/hva-h264.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>