mac/apphub: only instantiate log and option when in Application mode

when in libmpv mode there is no need to for logging and reading options.
this also prevents possible race conditions with the usage and deinit of
the mpv_handler.

osdep/mac/app_hub.swift

@@ -50,11 +50,13 @@ class AppHub: NSObject {
     }
 
     @objc func initMpv(_ mpv: OpaquePointer) {
-        log.log = mp_log_new(UnsafeMutablePointer(mpv), mp_client_get_log(mpv), "app")
-        option = OptionHelper(UnsafeMutablePointer(mpv), mp_client_get_global(mpv))
-        input.option = option
         event = EventHelper(self, mpv)
-        self.mpv = event?.mpv
+        if let mpv = event?.mpv {
+            self.mpv = mpv
+            log.log = mp_log_new(UnsafeMutablePointer(mpv), mp_client_get_log(mpv), "app")
+            option = OptionHelper(UnsafeMutablePointer(mpv), mp_client_get_global(mpv))
+            input.option = option
+        }
 
 #if HAVE_MACOS_MEDIA_PLAYER
         remote?.registerEvents()