[X86] Fix typo: QWORD alignment is greater than or equal to 8, not greater than 8 (#87819)

Align(8) is QWORD aligned, but this was checking to see if alignment was
greater than that, when it should have been checking for being greater
than OR EQUAL to Align(8).

This bug was introduced in
https://github.com/llvm/llvm-project/commit/6a6af30d433d7 during the
transition to the Align type.