IR: avoid name clashes between raised local functions.

compiler/testData/codegen/box/functions/localFunctions/nameClash.kt

@@ -0,0 +1,12 @@
+// IGNORE_BACKEND_FIR: JVM_IR
+
+fun test(b: Boolean): String {
+    if (b) {
+        fun result() = "OK"
+        return result()
+    } else {
+        fun result() = "Fail"
+        return result()
+    }
+}
+fun box(): String = test(true)