[media] staging: media: cxd2099: use kzalloc to allocate ci pointer of type struct...

[media] staging: media: cxd2099: use kzalloc to allocate ci pointer of type struct cxd in cxd2099_attach

this does kmalloc and followed by memset, calling kzalloc will actually
sets the allocated memory to zero, use kzalloc instead

Signed-off-by: Devendra Naga <develkernel412222@gmail.com>
Cc: Ralph Metzler <rjkm@metzlerbros.de>
Cc: Oliver Endriss <o.endriss@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>