[llvm] [X86] Fix typo: QWORD alignment is greater than 4, not 8 (PR #87819)

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AtariDreams wrote:

> But no tests are affected?

Align(8) is QWORD aligned, but this was checking to see f alignment was higher than that, which it is not.

Another PR I am working on for optsize depends on this, but because it is an oversight or typo that affects the compiler, I figure I would make this into a separate PR.

https://github.com/llvm/llvm-project/pull/87819