[MLGO] Add IR2Vec files to pr-subscribes-mlgo

Everything is in the title.

Author: boomanaiden154

.github/new-prs-labeler.yml

@@ -703,6 +703,10 @@ mlgo:
   - llvm/test/CodeGen/MLRegAlloc/**
   - llvm/utils/mlgo-utils/**
   - llvm/docs/MLGO.rst
+  - llvm/include/llvm/Analysis/IR2Vec.h
+  - llvm/lib/Analysis/IR2Vec.cpp
+  - llvm/lib/Analysis/models/**
+  - llvm/test/Analysis/IR2Vec/**
 
 tools:llvm-exegesis:
   - llvm/tools/llvm-exegesis/**