[Bugfix] fix custom op GmmSwigluQuantWeightNzTensorList (#4593)

### What this PR does / why we need it?

1. Fixes the environment path used to locate custom op shared libraries.
2. Uses empty tensor initialization for op outputs instead of
zero-initialization for better efficiency.



- vLLM version: v0.11.2
- vLLM main: https://github.com/vllm-project/vllm/commit/v0.11.2

---------

Signed-off-by: QianChenxi <chenxi.qian.cq@outlook.com>

CMakeLists.txt

@@ -131,6 +131,6 @@ target_link_libraries(
   opapi
 )
 
-target_link_options(vllm_ascend_C PRIVATE "-Wl,-rpath,$ORIGIN:$ORIGIN/lib")
+target_link_options(vllm_ascend_C PRIVATE "-Wl,-rpath,$ORIGIN:$ORIGIN/lib:$ORIGIN/_cann_ops_custom/vendors/vllm-ascend/op_api/lib")
 
 install(TARGETS vllm_ascend_C vllm_ascend_kernels DESTINATION ${VLLM_ASCEND_INSTALL_PATH})