[llvm] [BOLT][AArch64] Handle OpNegateRAState to enable optimizing binaries with pac-ret hardening (PR #120064)

[Paschalis Mpeis via llvm-commits]

================
@@ -250,6 +281,30 @@ class AArch64MCPlusBuilder : public MCPlusBuilder {
     }
   }
 
+  bool isPSignOnLR(const MCInst &Inst) const override {
+    ErrorOr<MCPhysReg> SignReg = getSignedReg(Inst);
+    if (SignReg && *SignReg != getNoRegister() && *SignReg == AArch64::LR)
+      return true;
+
+    return false;
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paschalis-mpeis wrote:

nit (similarly to next function): 
```suggestion
    return SignReg && *SignReg != getNoRegister() && *SignReg == AArch64::LR;
```

https://github.com/llvm/llvm-project/pull/120064