[llvm] [mlir] [MLIR][AMDGPU] Fixing word alignment check for bufferload fastpath (PR #135982)

[Zhuoran Yin via llvm-commits]

jerryyin wrote:

IREE CI help me caught a few bazel build related failures. (That won't reproduce in standlone upstream build). I'll leave this PR till tomorrow in case there's any additional review feedbacks on the new commit. Thanks for everyone's review!

https://github.com/llvm/llvm-project/pull/135982