[llvm] [PAC][CodeGen][ELF][AArch64] Support signed GOT (PR #96164)

[Fangrui Song via llvm-commits]

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@@ -85,6 +85,14 @@
 
    ldr x24, [x23, #:got_lo12:sym]
 // CHECK-ERROR: error: ILP32 64-bit load/store relocation not supported (LP64 eqv: LD64_GOT_LO12_NC)
+// CHECK-ERROR: ^
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MaskRay wrote:

Testing caret `^` is not really useful... To test diagnostics, just check the file and line information before `error:`

I'll adjust other diagnostics in the file.

https://github.com/llvm/llvm-project/pull/96164