[v3 linux] remove unused dialog callbacks

If it turns out these are needed in the future
we can add them back in then.

v3/pkg/application/linux_cgo.go

@@ -1133,46 +1133,3 @@ func runSaveFileDialog(dialog *SaveFileDialogStruct) (string, error) {
 
 	return results[0], nil
 }
-
-//export openFileDialogCallbackEnd
-func openFileDialogCallbackEnd(cid C.uint) {
-	id := uint(cid)
-	channel, ok := openFileResponses[id]
-	if ok {
-		close(channel)
-		delete(openFileResponses, id)
-		freeDialogID(id)
-	} else {
-		panic("No channel found for open file dialog")
-	}
-}
-
-//export openFileDialogCallback
-func openFileDialogCallback(cid C.uint, cpath *C.char) {
-	path := C.GoString(cpath)
-	id := uint(cid)
-	channel, ok := openFileResponses[id]
-	if ok {
-		channel <- path
-	} else {
-		panic("No channel found for open file dialog")
-	}
-}
-
-//export saveFileDialogCallback
-func saveFileDialogCallback(cid C.uint, cpath *C.char) {
-	// Covert the path to a string
-	path := C.GoString(cpath)
-	id := uint(cid)
-	// put response on channel
-	channel, ok := saveFileResponses[id]
-	if ok {
-		channel <- path
-		close(channel)
-		delete(saveFileResponses, id)
-		freeDialogID(id)
-
-	} else {
-		panic("No channel found for save file dialog")
-	}
-}