[llvm] [TableGen] Use PrintFatalError in ParseTreePattern when DAG has zero operands, so that llvm-tblgen doesn't crash (PR #161417)

[Prerona Chaudhuri via llvm-commits]

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@@ -19,21 +19,21 @@ def INSTR_BAR : Instruction {
 }
 
 #ifdef ERROR1
-// ERROR1: [[@LINE+1]]:1: error: {{.*}} Invalid number of type casts!
+// ERROR1: error: Invalid number of type casts!
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pchaudhuri-nv wrote:

Thank you for the feedback. I have made the changes...

Also, I would like to highlight that AI agents have helped here. Kindly let me know if the changes are fine now.

https://github.com/llvm/llvm-project/pull/161417