[lld] [LLD][ELF] Fix SHF_MERGE misalignment when spilled (PR #119289)

[Fangrui Song via llvm-commits]

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@@ -310,17 +310,19 @@ SECTIONS {
 .byte 0x12, 0x34
 
 .section .b,"aM", at progbits,1
+.p2align 1
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MaskRay wrote:

We also need to dump the section content (e.g. `-x second` )

https://github.com/llvm/llvm-project/pull/119289