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>

vllm_ascend/utils.py

@@ -49,7 +49,6 @@ ACL_FORMAT_FRACTAL_ND = 2
 ACL_FORMAT_FRACTAL_NZ = 29
 
 _CUSTOM_OP_ENABLED = None
-_SLEEP_MODE_ENABLED = None
 _CURRENT_STREAM = None
 _PREFETCH_STREAM = None
 _SHARED_EXPERTS_CALCULATION_STREAM = None
@@ -125,14 +124,6 @@ def is_enable_nz():
     return envs_ascend.VLLM_ASCEND_ENABLE_NZ
 
 
-def sleep_mode_enabled():
-    global _SLEEP_MODE_ENABLED
-    if _SLEEP_MODE_ENABLED is None:
-        from vllm_ascend import _build_info  # type: ignore
-        _SLEEP_MODE_ENABLED = _build_info.__sleep_mode_enabled__
-    return _SLEEP_MODE_ENABLED
-
-
 def _round_up(x: int, align: int):
     # round up x to align, for example, if align is 16, x will be rounded up to 16, 32, 48, etc.
     # input: 15, 16 -> output: 16