license: gsup: libosmogsm requires GPL, not AGPL; say 'sysmocom'

The copyright in gsup.h differed from the one in gsup.c: gsup.c names the GNU
Affero GPL, gsup.h only the GNU GPL. Change both to GPL-v2-or-later.

In gsup.c/h's copyright notice, 'sysmocom' should be spelled lower case.

Change-Id: Ia5748c275501889b9086aef7d20ccb5c9edb8031
2 files changed