use `torch.clamp`

[vincentzed]

Motivation

Motivated by the note in code, we should use torch.clamp cc @merrymercy if you could please look.

https://pytorch.org/docs/stable/generated/torch.clamp.html

Modifications

use torch.clamp for val

The torch.minimum function calculates the element-wise minimum between the seq_lens tensor and a scalar tensor self.sliding_window_size + 1. Now, no value in paged_kernel_lens_tmp exceeds self.sliding_window_size + 1. Values in seq_lens that are already less than or equal to this limit remain unchanged.

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