media: staging: media: atomisp: Don't do unnecessary zeroing of memory

In a few places in pci/sh_css_params.c, memset is used to zero memory
immediately before it is freed. As none of these structs appear to
contain sensitive information, just remove the calls to memset.

Suggested-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alex Dewar <alex.dewar90@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>