drm/amdgpu: information leak in amdgpu_info_ioctl()

We recently changed the drm_amdgpu_info_device struct so now there is
a 4 byte hole at the end.  We need to initialize it so we don't disclose
secret information from the stack.

Fixes: fa92754e ('drm/amdgpu: add VCE harvesting instance query')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

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

@@ -416,7 +416,7 @@ static int amdgpu_info_ioctl(struct drm_device *dev, void *data, struct drm_file
 		return n ? -EFAULT : 0;
 	}
 	case AMDGPU_INFO_DEV_INFO: {
-		struct drm_amdgpu_info_device dev_info;
+		struct drm_amdgpu_info_device dev_info = {};
 		struct amdgpu_cu_info cu_info;
 
 		dev_info.device_id = dev->pdev->device;