packages/Config.in: Alphabetical entries sorting

This patch moves :
  "Filesystem and flash utilities" menu
  "X applications" category
  "JSON/XML" menu
so they are in alphabetical order with the rest of the file.

Signed-off-by: Maxime Hadjinlian <maxime.hadjinlian@gmail.com>
Acked-by: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>