[Model] Optimizing gemma3 model's GemmaRMSNorm function (#3151)

### What this PR does / why we need it?
Before optimizing，the rmsnorm time in one decoding is 531.5us. After
optimizing，the rmsnorm time in one decoding is 105us.
I closed the previous
PR（https://github.com/vllm-project/vllm-ascend/pull/2456） by mistake and
resubmitted it now
### Does this PR introduce _any_ user-facing change?
No
### How was this patch tested?

- vLLM version: v0.10.2
- vLLM main:
b1068903fd

---------

Signed-off-by: socrahow <suzihao4@h-partners.com>

vllm_ascend/utils.py

@@ -505,7 +505,8 @@ def register_ascend_customop(vllm_config: Optional[VllmConfig] = None):
     from vllm_ascend.ops.activation import AscendQuickGELU, AscendSiluAndMul
     from vllm_ascend.ops.common_fused_moe import (AscendFusedMoE,
                                                   AscendSharedFusedMoE)
-    from vllm_ascend.ops.layernorm import AscendQuantRMSNorm, AscendRMSNorm
+    from vllm_ascend.ops.layernorm import (AscendGemmaRMSNorm,
+                                           AscendQuantRMSNorm, AscendRMSNorm)
     from vllm_ascend.ops.linear import (AscendColumnParallelLinear,
                                         AscendMergedColumnParallelLinear,
                                         AscendQKVParallelLinear,
@@ -530,6 +531,7 @@ def register_ascend_customop(vllm_config: Optional[VllmConfig] = None):
         "ParallelLMHead": AscendParallelLMHead,
         "LogitsProcessor": AscendLogitsProcessor,
         "RMSNorm": AscendRMSNorm,
+        "GemmaRMSNorm": AscendGemmaRMSNorm,
         "FusedMoE": AscendFusedMoE,
         "SharedFusedMoE": AscendSharedFusedMoE,
         "MultiHeadLatentAttention": AscendMultiHeadLatentAttention,