Replaced deprecated inline classes with JvmInline value classes in tests

compiler/testData/codegen/box/inlineClasses/kt25750.kt

@@ -1,4 +1,3 @@
-// !LANGUAGE: +InlineClasses
 // WITH_RUNTIME
 
 import kotlin.reflect.KMutableProperty0
@@ -7,7 +6,8 @@ import kotlin.reflect.KProperty
 operator fun <R> KMutableProperty0<R>.setValue(host: Any?, property: KProperty<*>, value: R) = set(value)
 operator fun <R> KMutableProperty0<R>.getValue(host: Any?, property: KProperty<*>): R = get()
 
-inline class Foo(val i: Int)
+@JvmInline
+value class Foo(val i: Int)
 
 var f = Foo(4)