media: Staging: atomisp: fix alloc_cast.cocci warnings

Remove casting the values returned by memory allocation functions
like kmalloc, kzalloc, kmem_cache_alloc, kmem_cache_zalloc etc.

Semantic patch information:
This makes an effort to find cases of casting of values returned by
kmalloc, kzalloc, kcalloc, kmem_cache_alloc, kmem_cache_zalloc,
kmem_cache_alloc_node, kmalloc_node and kzalloc_node and removes
the casting as it is not required. The result in the patch case may
need some reformatting.

Generated by: scripts/coccinelle/api/alloc/alloc_cast.cocci

Signed-off-by: Branislav Radocaj <branislav@radocaj.org>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>