backend/tests: Add blackbox tests from Kotlin JVM

Added tests from testData/codegen/box directory. There are blackbox tests
in other directories and they are to be added.

backend.native/tests/external/codegen/blackbox/dataClasses/equals/genericarray.kt

@@ -0,0 +1,8 @@
+data class A(val v: Array<Int>)
+
+fun box() : String {
+  val myArray = arrayOf(0, 1, 2)
+  if(A(myArray) == A(arrayOf(0, 1, 2))) return "fail"
+  if(A(myArray) != A(myArray)) return "fail 2"
+  return "OK"
+}