nx-libs.spec file license says GPLv2+, should be GPLv2 (only)

[Apteryks]

Hi,

https://github.com/ArcticaProject/nx-libs/blob/e18eb77f397b72c1a10141d2bafa2dc975ab7d38/nx-libs.spec#L21 says the license is GPLv2 or later, while the actual license of the combined works is GPLv2 only.