virtio/s390: virtio: constify virtio_config_ops structures

Declare virtio_config_ops structure as const as it is only stored in the
config field of a virtio_device structure. This field is of type const, so
virtio_config_ops structures having this property can be declared const.
Done using Coccinelle:

@r1 disable optional_qualifier@
identifier i;
position p;
@@
static struct virtio_config_ops i@p={...};

@ok1@
identifier r1.i;
position p;
struct virtio_ccw_device x;
@@
x.vdev.config=&i@p

@bad@
position p!={r1.p,ok1.p};
identifier r1.i;
@@
i@p

@depends on !bad disable optional_qualifier@
identifier r1.i;
@@
+const
struct virtio_config_ops i;

File size before and after applying the patch remains the same.
text	data	bss	dec	hex   filename
9235	296	32928	42459	a5db  drivers/s390/virtio/virtio_ccw.o

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Message-Id: <1484333336-13443-1-git-send-email-bhumirks@gmail.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>