Fix tests: "infix modifier required" and "operator modifier required" errors

compiler/testData/codegen/box/extensionProperties/genericValForPrimitiveType.kt

@@ -11,7 +11,7 @@ class A {
     val char: Char = '0'
     val bool: Boolean = false
 
-    fun invoke() {
+    operator fun invoke() {
         int.valProp
         long.valProp
         short.valProp

compiler/testData/codegen/box/extensionProperties/genericVarForPrimitiveType.kt

@@ -12,7 +12,7 @@ class A {
     var char: Char = '0'
     var bool: Boolean = false
 
-    fun invoke() {
+    operator fun invoke() {
         int.varProp = int
         long.varProp = long
         short.varProp = short