media: s3c-camif: make array 'registers' static const, makes object smaller

Don't populate the array 'registers' on the stack but instead make it
static const. Makes the object code smaller by 45 bytes.

Before:
   text	   data	    bss	    dec	    hex	filename
  17364	   5000	      0	  22364	   575c	platform/s3c-camif/camif-regs.o

After:
   text	   data	    bss	    dec	    hex	filename
  17255	   5064	      0	  22319	   572f	platform/s3c-camif/camif-regs.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+samsung@kernel.org>