drm/amdkfd: Remove unnecessary NULL values

The NULL initialization of the pointers assigned by kzalloc() first is
not necessary, because if the kzalloc() failed, the pointers will be
assigned NULL, otherwise it works as usual. so remove it.
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdkfd/kfd_mqd_manager.c

@@ -48,7 +48,7 @@ int pipe_priority_map[] = {
 
 struct kfd_mem_obj *allocate_hiq_mqd(struct kfd_node *dev, struct queue_properties *q)
 {
-	struct kfd_mem_obj *mqd_mem_obj = NULL;
+	struct kfd_mem_obj *mqd_mem_obj;
 
 	mqd_mem_obj = kzalloc(sizeof(struct kfd_mem_obj), GFP_KERNEL);
 	if (!mqd_mem_obj)
@@ -64,7 +64,7 @@ struct kfd_mem_obj *allocate_hiq_mqd(struct kfd_node *dev, struct queue_properti
 struct kfd_mem_obj *allocate_sdma_mqd(struct kfd_node *dev,
 					struct queue_properties *q)
 {
-	struct kfd_mem_obj *mqd_mem_obj = NULL;
+	struct kfd_mem_obj *mqd_mem_obj;
 	uint64_t offset;
 
 	mqd_mem_obj = kzalloc(sizeof(struct kfd_mem_obj), GFP_KERNEL);