[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 +1,22 @@
+# RUN: llvm-mc --filetype=obj --triple=loongarch64 --mattr=+relax %s \
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SixWeining wrote:

It could be better to add a description about the aim of this test. For example:
```
## Check R_LARCH_ALIGN is not generated for non executable section.
```

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