Revert "Adding cpu inference with VXE ISA for s390x architecture (#12613)

[WoosukKwon]

This reverts commit ada1921. (PR #12613)

[github-actions]

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[dilipgb]

@WoosukKwon I request not to proceed with the revert before we discuss and conclude on the needs.

I have replied to your comments on other PR. Please check it once.