KT-6916 Slow bytecode for downTo iteration like for (i in max downTo min)

#KT-6916 fixed

compiler/testData/codegen/bytecodeText/forLoop/primitiveRange.kt

@@ -0,0 +1,8 @@
+fun f(r: IntRange) {
+    for (i in r) {
+    }
+}
+
+// 0 iterator
+// 1 getStart
+// 1 getEnd