Remove COMPILE_CUSTOM_KERNELS env (#4864)

With more and more custom ops merged, disable `COMPILE_CUSTOM_KERNELS `
for vllm ascend seems useless now. Let's enable csrc compile by default.

- vLLM version: v0.12.0
- vLLM main:
ad32e3e19c

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

setup.py

@@ -165,16 +165,10 @@ def gen_build_info():
     assert soc_version in soc_to_device, f"Undefined soc_version: {soc_version}. Please file an issue to vllm-ascend."
     device_type = soc_to_device[soc_version]
 
-    if device_type == "_310P" and not envs.COMPILE_CUSTOM_KERNELS:
-        raise ValueError(
-            "device type 310P only supports custom kernels. Please set COMPILE_CUSTOM_KERNELS=1 to enable custom kernels."
-        )
-
     package_dir = os.path.join(ROOT_DIR, "vllm_ascend", "_build_info.py")
     with open(package_dir, "w+") as f:
         f.write('# Auto-generated file\n')
         f.write(f"__device_type__ = '{device_type}'\n")
-        f.write(f"__sleep_mode_enabled__ = {envs.COMPILE_CUSTOM_KERNELS}\n")
     logging.info(f"Generated _build_info.py with SOC version: {soc_version}")
 
 
@@ -357,8 +351,6 @@ class cmake_build_ext(build_ext):
         )
 
     def build_extensions(self) -> None:
-        if not envs.COMPILE_CUSTOM_KERNELS:
-            return
         # Ensure that CMake is present and working
         try:
             subprocess.check_output(["cmake", "--version"])
@@ -450,9 +442,7 @@ except LookupError:
     # only checks out the commit. In this case, we set a dummy version.
     VERSION = "0.0.0"
 
-ext_modules = []
-if envs.COMPILE_CUSTOM_KERNELS:
-    ext_modules = [CMakeExtension(name="vllm_ascend.vllm_ascend_C")]
+ext_modules = [CMakeExtension(name="vllm_ascend.vllm_ascend_C")]
 
 
 def get_path(*filepath) -> str: