Report diagnostics for inline classes even if the feature is unsupported

This would help for those who use inline classes by suppressing error
 about unsupported feature

compiler/testData/diagnostics/tests/inlineClasses/basicInlineClassDeclarationDisabled.kt

@@ -1,7 +1,10 @@
 // !LANGUAGE: -InlineClasses
+// !DIAGNOSTICS: -UNUSED_PARAMETER
 
 <!UNSUPPORTED_FEATURE!>inline<!> class Foo(val x: Int)
 
 <!WRONG_MODIFIER_TARGET!>inline<!> annotation class InlineAnn
 <!WRONG_MODIFIER_TARGET!>inline<!> object InlineObject
 <!WRONG_MODIFIER_TARGET!>inline<!> enum class InlineEnum
+
+<!UNSUPPORTED_FEATURE!>inline<!> class NotVal(<!INLINE_CLASS_CONSTRUCTOR_NOT_FINAL_READ_ONLY_PARAMETER!>x: Int<!>)