[lld] [LLD][ELF][AArch64] Mark .plt and .iplt with PURECODE flag (PR #134798)

[Csanád Hajdú via llvm-commits]

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@@ -14,6 +14,7 @@
 // CHECKDSO:     Name: .plt
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Il-Capitano wrote:

You'd need `llvm-readelf -l` for that, which could be separate from the `llvm-readobj` tests. Should I just add an extra `llvm-readelf -l` line or use `llvm-readelf` for everything?

Also, I guess aarch64-gnu-ifunc-plt.s could be converted in the same way?

https://github.com/llvm/llvm-project/pull/134798