[llvm] [SPIR-V] Fix bad insertion for type/id MIR (PR #109686)

[Nathan Gauër via llvm-commits]

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@@ -336,6 +347,7 @@ class SPIRVGlobalRegistry {
   MachineFunction *setCurrentFunc(MachineFunction &MF) {
     MachineFunction *Ret = CurMF;
     CurMF = &MF;
+    LastInsertedType = nullptr;
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Keenuts wrote:

Ahh thought we traversed each function once. Makes sense. I'll move that into a map so we can save context.

https://github.com/llvm/llvm-project/pull/109686