[llvm] [LoongArch] Insert nops and emit align reloc when handle alignment directive (PR #72962)

[Lu Weining via llvm-commits]

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@@ -0,0 +1,53 @@
+# RUN: llvm-mc --filetype=obj --triple=loongarch64 --mattr=-relax %s \
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SixWeining wrote:

- Ditto. Add a file-level comment.
- Use -o to save the output file so that we can copy  and execute the command easily.
- Is is better to use `llvm-objdump -dr` to check the result?
- --check-prefix

https://github.com/llvm/llvm-project/pull/72962