drm/amdgpu: Remove a redundant sanity check

The case where 'num_entries' is too big, is already handled by
struct_size(), because kvmalloc() would fail.

It will return -ENOMEM instead of -EINVAL, but it is only related to a
unlikely to happen sanity check.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c

@@ -78,10 +78,6 @@ int amdgpu_bo_list_create(struct amdgpu_device *adev, struct drm_file *filp,
 	unsigned i;
 	int r;
 
-	if (num_entries > (SIZE_MAX - sizeof(struct amdgpu_bo_list))
-				/ sizeof(struct amdgpu_bo_list_entry))
-		return -EINVAL;
-
 	list = kvmalloc(struct_size(list, entries, num_entries), GFP_KERNEL);
 	if (!list)
 		return -ENOMEM;