[FIR] Add inline checker for bodies of inline functions

This checker doesn't support `@PublishedAPI` yet, so some BB tests for it
 were muted. #KT-46270

compiler/testData/diagnostics/tests/inline/wrongUsage.kt

@@ -1,3 +1,4 @@
+// FIR_IDENTICAL
 // !DIAGNOSTICS: -UNUSED_EXPRESSION -UNUSED_PARAMETER -UNUSED_VARIABLE -ASSIGNED_BUT_NEVER_ACCESSED_VARIABLE -UNUSED_VALUE -NOTHING_TO_INLINE -USELESS_ELVIS
 
 inline fun inlineFunWrongUsage(s: (p: Int) -> Unit) {
@@ -48,4 +49,4 @@ inline fun inlineFunNoInline(noinline ext: Int.(p: Int) -> Unit) {
     if (true) ext else 0
 
     ext ?: ext
-}
+}