[NFC] Move ARM `opt -indvars` test from Codegen into Transforms

They are really not codegen tests.
diff --git a/llvm/test/CodeGen/ARM/indvar-cost.ll b/llvm/test/Transforms/IndVarSimplify/ARM/indvar-cost.ll
similarity index 100%
rename from llvm/test/CodeGen/ARM/indvar-cost.ll
rename to llvm/test/Transforms/IndVarSimplify/ARM/indvar-cost.ll
diff --git a/llvm/test/CodeGen/ARM/indvar-unroll-imm-cost.ll b/llvm/test/Transforms/IndVarSimplify/ARM/indvar-unroll-imm-cost.ll
similarity index 100%
rename from llvm/test/CodeGen/ARM/indvar-unroll-imm-cost.ll
rename to llvm/test/Transforms/IndVarSimplify/ARM/indvar-unroll-imm-cost.ll
diff --git a/llvm/test/Transforms/IndVarSimplify/ARM/lit.local.cfg b/llvm/test/Transforms/IndVarSimplify/ARM/lit.local.cfg
new file mode 100644
index 0000000..236e1d3
--- /dev/null
+++ b/llvm/test/Transforms/IndVarSimplify/ARM/lit.local.cfg
@@ -0,0 +1,2 @@
+if not 'ARM' in config.root.targets:
+    config.unsupported = True