[EPLB] Avoiding eplb's dependency on a specified model (#6528)

### What this PR does / why we need it?
1. Currently, eplb registers different attributes for different models,
but these attributes are not actually used. Now, these attributes are
directly deleted.
2. Add some log about eplb.

### Does this PR introduce _any_ user-facing change?

### How was this patch tested?
#### Deepseek v3.1 chat
Of course! Here is a comprehensive explanation of deep learning, broken
down for clarity.\n\n### The Simple Analogy: A Child Learning to
Recognize a Cat\n\nImagine teaching a child what a cat is. You don't
give them a rulebook with instructions like \"has pointy ears, whiskers,
and a tail.\" Instead, you show them many pictures, saying \"this is a
cat\" or \"this is not a cat.\" The child's brain gradually learns to
identify the complex patterns—the combination of shapes, colors, and
textures—that define \"cat-ness.\"\n\n**Deep learning is essentially
this, but for computers.** It's a method for teaching computers to learn
from examples and recognize patterns directly from data (like images,
sound, or text) without being explicitly programmed with rigid
rules.\n\n---\n\n### The Technical Definition\n\n**Deep Learning is a
subfield of machine learning, which itself is a subfield of artificial
intelligence (AI).** It uses artificial **neural networks** with many
layers (\"deep\" networks) to model and understand complex patterns in
data.\n\nHere are the key concepts in that definition:\n\n1.
**Artificial Intelligence (AI):** The broad science of making machines
smart and capable of performing tasks that typically require human
intelligence.\n2. **Machine Learning (ML):** A subset of AI that gives
computers the ability to learn from data *without* being explicitly
programmed for every single rule.\n3. **Deep Learning (DL):** A
specific, powerful

- vLLM version: v0.15.0
- vLLM main: https://github.com/vllm-project/vllm/commit/v0.15.0

Signed-off-by: shenchuxiaofugui <1311027364@qq.com>

vllm_ascend/ascend_config.py

@@ -385,6 +385,7 @@ class EplbConfig:
 
     def _validate_config(self):
         if self.expert_map_path is not None:
+            logger.info(f"The expert_map is {self.config['dynamic_eplb']}")
             if self.expert_map_path[-5:] != ".json":
                 raise TypeError("The expert_map is not json.")
             if not os.path.exists(self.expert_map_path):
@@ -402,6 +403,14 @@ class EplbConfig:
                 raise ValueError(f"{key} must greater than 0; got {self.config[key]} instead")
         if self.eplb_policy_type not in [0, 1, 2, 3]:
             raise ValueError("eplb_policy_type must in [0, 1, 2, 3]")
+        if self.config["dynamic_eplb"]:
+            assert (
+                os.getenv("DYNAMIC_EPLB", "false").lower() in ("true", "1")
+                or os.getenv("EXPERT_MAP_RECORD", "false") == "true"
+            ), "The environment variable DYNAMIC_EPLB or EXPERT_MAP_RECORD of the ePLB must be set to true."
+
+        logger.info(f"Dynamic EPLB is {self.config['dynamic_eplb']}")
+        logger.info(f"The number of redundant experts is {self.config['num_redundant_experts']}")
 
 
 _ASCEND_CONFIG: AscendConfig | None = None