package/wireless-regdb: bump version to 2018.05.31

Added license hash, updated project URL, old site is dead.

Signed-off-by: Bernd Kuhls <bernd.kuhls@t-online.de>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
(cherry picked from commit 54917abdd74158298fd848a58117c796c641a130)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
3 files changed