[lld] [ELF] Fix unnecessary inclusion of unreferenced provide symbols (PR #84512)

[Fangrui Song via llvm-commits]

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@@ -40,13 +51,23 @@ patatino:
   movl newsym, %eax
 
 #--- chain.t
-PROVIDE(f2 = 0x1000);
+PROVIDE(f7 = 0x1000);
+PROVIDE(f5 = f6);
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MaskRay wrote:

Add a cycle example to either this test or the new test?

https://github.com/llvm/llvm-project/pull/84512