[Refactor] refactor patch module (#3555)

### What this PR does / why we need it?
we notice that `patch_main` is never used. Usually the patch is for all
version. And if it's for specified version, we can use `vllm_version_is`
instead. So let's remove the useless sub folder in patch module to make
it clear.


- vLLM version: v0.11.0rc3
- vLLM main: https://github.com/vllm-project/vllm/commit/v0.11.0

Signed-off-by: wangxiyuan <wangxiyuan1007@gmail.com>

vllm_ascend/patch/platform/__init__.py

@@ -14,5 +14,11 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from vllm_ascend.patch.platform import patch_common  # noqa: F401
-from vllm_ascend.patch.platform import patch_main  # noqa: F401
+import os
+
+import vllm_ascend.patch.platform.patch_config  # noqa
+import vllm_ascend.patch.platform.patch_distributed  # noqa
+import vllm_ascend.patch.platform.patch_mamba_config  # noqa
+
+if os.getenv("DYNAMIC_EPLB", False) or os.getenv("EXPERT_MAP_RECORD", False):
+    import vllm_ascend.patch.platform.patch_multiproc_executor  # noqa