Fix equals check in interpreter in case when object is wrapped as Proxy

compiler/testData/ir/interpreter/proxy/customEquals.kt

@@ -1,5 +1,18 @@
 import kotlin.collections.*
 
+@CompileTimeCalculation
+class A(val a: Int) {
+    override fun equals(other: Any?): Boolean {
+        return other is Int && other == a
+    }
+}
+const val customEquals1 = <!EVALUATED: `true`!>A(1) == 1<!>
+const val customEquals2 = <!EVALUATED: `false`!>A(1) == 123<!>
+const val customEquals3 = <!EVALUATED: `false`!>1 == A(1)<!>
+const val customEquals4 = <!EVALUATED: `false`!>123 == A(1)<!>
+const val customEquals5 = <!EVALUATED: `false`!>null == A(1)<!>
+const val customEquals6 = <!EVALUATED: `false`!>A(1) == null<!>
+
 @CompileTimeCalculation
 class B(val b: Int) {
     override fun equals(other: Any?): Boolean {