[shotwell] Fix compile error after GPhoto vapi change

[Jens Georg <jensgeorg src gnome org>]

commit 0c5779bf9d9fa8f08696340dff1548b3c25374c6
Author: Jens Georg <mail jensge org>
Date:   Sun Mar 14 11:21:10 2021 +0100

    Fix compile error after GPhoto vapi change

 src/camera/ImportPage.vala | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/camera/ImportPage.vala b/src/camera/ImportPage.vala
index f5e98955..7dbe9d42 100644
--- a/src/camera/ImportPage.vala
+++ b/src/camera/ImportPage.vala
@@ -1333,7 +1333,7 @@ public class ImportPage : CheckerboardPage {
         if (fsid >= sifs.length)
             return null;
         
-        return (sifs[fsid].fields & GPhoto.CameraStorageInfoFields.BASE) != 0 ? sifs[fsid].basedir : "/";
+        return (GPhoto.CameraStorageInfoFields.BASE in sifs[fsid].fields) ? (string) sifs[fsid].basedir : 
"/";
     }
     
     public static string? get_fulldir(GPhoto.Camera camera, string camera_name, int fsid, string folder) {