[Deprecation] Deprecate seed_everything and scatter_mm_placeholders in v0.15 (#33362)

Signed-off-by: yewentao256 <zhyanwentao@126.com>

vllm/platforms/interface.py

@@ -4,14 +4,11 @@ import contextlib
 import enum
 import os
 import platform
-import random
 import sys
 from datetime import timedelta
 from typing import TYPE_CHECKING, Any, NamedTuple
 
-import numpy as np
 import torch
-from typing_extensions import deprecated
 
 from vllm.logger import init_logger
 from vllm.v1.attention.backends.registry import AttentionBackendEnum
@@ -365,23 +362,6 @@ class Platform:
         """
         return torch.inference_mode(mode=True)
 
-    @classmethod
-    @deprecated(
-        "`seed_everything` is deprecated. It will be removed in v0.15.0 or later. "
-        "Please use `vllm.utils.torch_utils.set_random_seed` instead."
-    )
-    def seed_everything(cls, seed: int | None = None) -> None:
-        """
-        Set the seed of each random module.
-        `torch.manual_seed` will set seed on all devices.
-
-        Loosely based on: https://github.com/Lightning-AI/pytorch-lightning/blob/2.4.0/src/lightning/fabric/utilities/seed.py#L20
-        """
-        if seed is not None:
-            random.seed(seed)
-            np.random.seed(seed)
-            torch.manual_seed(seed)
-
     @classmethod
     def set_device(cls, device: torch.device) -> None:
         """