Fix minor issue with :Interop:Indexer:updatePrebuilt Gradle task

Interop/Indexer/build.gradle

@@ -14,6 +14,8 @@
  * limitations under the License.
  */
 
+import org.jetbrains.kotlin.konan.target.HostManager
+
 buildscript {
     apply from: "$rootDir/gradle/kotlinGradlePlugin.gradle"
 }
@@ -151,7 +153,7 @@ task updatePrebuilt {
         }
 
         copy {
-            from("$buildDir/nativelibs") {
+            from("$buildDir/nativelibs/${HostManager.host.visibleName}") {
                 include 'clangstubs.c'
             }
             into 'prebuilt/nativeInteropStubs/c'