Fix companion field access from inline class

#KT-26858

compiler/testData/codegen/box/inlineClasses/membersAccess/toPrivateCompanionVal.kt

@@ -0,0 +1,12 @@
+// !LANGUAGE: +InlineClasses
+// IGNORE_BACKEND: JVM_IR
+
+inline class R(private val r: Int) {
+    fun test() = pv
+
+    companion object {
+        private val pv = "OK"
+    }
+}
+
+fun box() = R(0).test()