Use more specific error for secondary constructor bodies in inline classes

- Also, this error allows IDE to provide quick-fix that changes language
 version in a project that simplifies the adoption
 - There is no point in
 changing K2 part as there this feature will be enabled by default

 ^KT-56224 Fixed

compiler/testData/diagnostics/tests/inlineClasses/reservedConstructorsBodyInKotlinPre19.kt

@@ -0,0 +1,9 @@
+// !LANGUAGE: -ValueClassesSecondaryConstructorWithBody
+// WITH_STDLIB
+
+@JvmInline
+value class Foo(val x: String) {
+    constructor(i: Int) : this(i.toString()) <!UNSUPPORTED_FEATURE!>{<!>
+        println(i)
+    }
+}