curl: fix/bump PKG_RELEASE, remove maintainer

* make PKG_RELEASE numeric again
* made a release bump due to  a newly added patch (see https://github.com/openwrt/packages/commit/de4ef9d169a182350796afca778742bf68052af4

 for details)
* remove maintainer (as requested in #23890

Signed-off-by: Dirk Brenken <dev@brenken.org>