Remove redundant assignment in xfer_buffers, This is a little fix

[ChenTaoyu-SJTU]

Purpose

Remove the redundant assignment of xfer_buffers in nixl_connector.py. The before code already handle the xfer_buffers in here:

        if self.use_host_buffer:
            self.initialize_host_xfer_buffer(kv_caches=kv_caches)
            assert len(self.host_xfer_buffers) == len(kv_caches), (
                f"host_buffer: {len(self.host_xfer_buffers)}, "
                f"kv_caches: {len(kv_caches)}")
            xfer_buffers = self.host_xfer_buffers
        else:
            xfer_buffers = kv_caches
            assert not self.host_xfer_buffers, (
                "host_xfer_buffer should not be initialized when "
                f"kv_buffer_device is {self.kv_buffer_device}")

        logger.info(
            "Registering KV_Caches. use_mla: %s, kv_buffer_device: %s, "
            "use_host_buffer: %s", self.use_mla, self.kv_buffer_device,
            self.use_host_buffer)

        caches_data = []
        # With hybrid allocator, layers can share a kv cache tensor
        seen_base_addresses = []

        # I removed the below redundant code
        xfer_buffers = (self.host_xfer_buffers
                        if self.use_host_buffer else kv_caches)

As can be seen above, the redundant assignment could be removed.

Test Plan

By pass CI

Test Result

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[gemini-code-assist]

Code Review

This pull request removes a redundant assignment to the xfer_buffers variable in the register_kv_caches method within nixl_connector.py. The variable was already correctly assigned in a preceding if/else block, making the subsequent assignment unnecessary. The change is correct and improves code clarity and maintainability by eliminating redundant code. I approve of this change.

[ChenTaoyu-SJTU]

@NickLucche This is ready for review

[njhill]

Thanks @ChenTaoyu-SJTU