[core] Support custom ascendc kernels in vllm-ascend (#233)

This PR add custom ascendc kernel rotary_embedding support in
vllm-ascend, related CMakeLists and setuptools is also added in this PR.

Related: https://github.com/vllm-project/vllm-ascend/issues/156

---------

Signed-off-by: ganyi <pleaplusone.gy@gmail.com>

csrc/ops.h

@@ -0,0 +1,32 @@
+/*
+ * Copyright (c) Huawei Technologies Co., Ltd. 2024. All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <optional>
+#include <torch/library.h>
+
+#include <vector>
+#include "kernels/types.h"
+
+namespace vllm_ascend {
+  extern void rotary_embedding_impl(AscendType type, bool isNeox, void *stream, int64_t *positions, void *queryDst,
+    void *keyDst, void *query, void *key, void *cosSinCache, const int rotDim,
+    const int64_t queryStride, const int64_t keyStride, const int64_t dstQueryStride,
+    const int64_t dstKeyStride, const int numHeads, const int numKvHeads,
+    const int headSize, const int64_t numTokens, const uint32_t loopCnt,
+    uint32_t aivNum);
+}