package/shairport-sync: bump to version 2.4.1

- Remove backported from upstream patch.
- Fix autoreconf comment that was wrong.

Signed-off-by: Jörg Krause <joerg.krause@embedded.rocks>
Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>