Unused symbol: handle imports from nested objects correctly

So #KT-17437 Fixed

idea/testData/inspectionsLocal/unusedSymbol/companionViaImport.kt

@@ -0,0 +1,14 @@
+// PROBLEM: none
+
+import My.Companion.create
+
+class <caret>My {
+    companion object {
+        fun create() = My()
+    }
+}
+
+fun test() {
+    val my = create()
+    my.hashCode()
+}