Fix T75589: Image Sequences have no data on file load.

Issue was with setting of frame to load from an image sequence,
synchronization was not done properly at some point, leading to
generation of an invalid final filepath to be read.

source/blender/blenkernel/intern/image.c

@@ -3977,7 +3977,9 @@ static ImBuf *load_sequence_single(
     iuser_t = *iuser;
   }
   else {
-    /* TODO(sergey): Do we need to initialize something here? */
+    /* BKE_image_user_file_path() uses this value for file name for sequences. */
+    iuser_t.framenr = frame;
+    /* TODO(sergey): Do we need to initialize something else here? */
   }
 
   iuser_t.view = view_id;