[Megatron] fix: compatible to mcore0.15 (volcengine#3534)

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Author: ISEEKYAN

verl/workers/megatron_workers.py

@@ -199,7 +199,6 @@ def __init__(self, config: DictConfig, role: str, **kwargs):
                 tensor_model_parallel_size=self.config.actor.megatron.tensor_model_parallel_size,
                 pipeline_model_parallel_size=self.config.actor.megatron.pipeline_model_parallel_size,
                 virtual_pipeline_model_parallel_size=self.config.actor.megatron.virtual_pipeline_model_parallel_size,
-                pipeline_model_parallel_split_rank=None,
                 use_sharp=False,
                 context_parallel_size=self.config.actor.megatron.context_parallel_size,
                 expert_model_parallel_size=self.config.actor.megatron.expert_model_parallel_size,
@@ -844,7 +843,6 @@ def __init__(self, config: McoreCriticConfig):
                 tensor_model_parallel_size=self.config.megatron.tensor_model_parallel_size,
                 pipeline_model_parallel_size=self.config.megatron.pipeline_model_parallel_size,
                 virtual_pipeline_model_parallel_size=self.config.megatron.virtual_pipeline_model_parallel_size,
-                pipeline_model_parallel_split_rank=None,
                 use_sharp=False,
                 context_parallel_size=self.config.megatron.context_parallel_size,
                 expert_model_parallel_size=self.config.megatron.expert_model_parallel_size,
@@ -1126,7 +1124,6 @@ def __init__(self, config):
                 tensor_model_parallel_size=self.config.megatron.tensor_model_parallel_size,
                 pipeline_model_parallel_size=self.config.megatron.pipeline_model_parallel_size,
                 virtual_pipeline_model_parallel_size=self.config.megatron.virtual_pipeline_model_parallel_size,
-                pipeline_model_parallel_split_rank=None,
                 use_sharp=False,
                 context_parallel_size=self.config.megatron.context_parallel_size,
                 expert_model_parallel_size=self.config.megatron.expert_model_parallel_size,