package/wavpack: bump to version 5.3.0
Update hash of COPYING (update in year):
https://github.com/dbry/WavPack/commit/350b6d7737383029573ea2cce9bd94f1b6756bbd
Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>