Made vararg parameters have Array<out T> type

instead of simply Array<T>
  #KT-1638 Fixed
  #KT-2163 Fixed
  #KT-3213 Fixed
  #KT-4172 Fixed
  #KT-5534 Fixed

compiler/testData/codegen/box/diagnostics/vararg/kt4172.kt

@@ -0,0 +1,14 @@
+fun box(): String {
+    main(array())
+    return "OK"
+}
+
+fun main(args: Array<String>) {
+    D.foo(array())
+}
+
+object D {
+    fun foo(array: Array<out String>) = array
+}
+
+inline fun <reified T> array(vararg t : T) : Array<T> = t as Array<T>