"field": deprecated warnings introduced, compiler tests migrated to the new syntax

compiler/testData/writeFlags/property/classObject/class/publicValNonDefault.kt

@@ -2,7 +2,7 @@ class Test {
   companion object {
     public val prop: Int = 0
       get() {
-        return $prop
+        return field
       }
   }
 }

compiler/testData/writeFlags/property/classObject/class/publicVarNonDefault.kt

@@ -2,7 +2,7 @@ class Test {
   companion object {
     public var prop: Int = 0
       set(i : Int) {
-        $prop = i
+        field = i
       }
   }
 }

compiler/testData/writeFlags/property/classObject/trait/publicValNonDefault.kt

@@ -2,7 +2,7 @@ interface Test {
   companion object {
     public val prop: Int = 0
       get() {
-        return $prop
+        return field
       }
   }
 }

compiler/testData/writeFlags/property/classObject/trait/publicVarNonDefault.kt

@@ -2,7 +2,7 @@ interface Test {
   companion object {
     public var prop: Int = 0
       set(i : Int) {
-        $prop = i
+        field = i
       }
   }
 }