gnome-panel3: move as-needed.patch to gnome-panel dir

* there is BPN changed to gnome-panel and SRC_URI checksuming code cannot find it, causing this warning:
  WARNING: Unable to get checksum for gnome-panel3-native SRC_URI entry as-needed.patch: file could not be found

Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>
Signed-off-by: Koen Kooi <koen@dominion.thruhere.net>