[llvm] [ARM][TableGen][MC] Change the ARM mnemonic operands to be optional for ASM parsing (PR #83436)

[Sergei Barannikov via llvm-commits]

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@@ -7050,29 +7098,24 @@ bool ARMAsmParser::ParseInstruction(ParseInstructionInfo &Info, StringRef Name,
   }
 
   // Add the carry setting operand, if necessary.
-  if (CanAcceptCarrySet) {
+  if (CanAcceptCarrySet && CarrySetting != 0) {
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s-barannikov wrote:

```suggestion
  if (CanAcceptCarrySet && CarrySetting) {
```

https://github.com/llvm/llvm-project/pull/83436