Changes

cgit: fix Atom feed hostname from localhost to cgit.osmocom.org

Before:
$ curl -s https://cgit.osmocom.org/libosmocore/ | grep "Atom feed"
<link rel='alternate' title='Atom feed' href='http://localhost/libosmocore/atom/?h=master' type='application/atom+xml'/>

After:
$ curl -s https://cgit.osmocom.org/libosmocore/ | grep "Atom feed"
<link rel='alternate' title='Atom feed' href='http://cgit.osmocom.org/libosmocore/atom/?h=master' type='application/atom+xml'/>

Change-Id: Iaab14e254acc0356f0d3639924e3b6b528d57973

cgit: Fix Atom feed scheme from http to https

before:
<link rel='alternate' title='Atom feed' href='http://cgit.osmocom.org/libosmocore/atom/?h=master' type='application/atom+xml'/>

after:
<link rel='alternate' title='Atom feed' href='https://cgit.osmocom.org/libosmocore/atom/?h=master' type='application/atom+xml'/>

Change-Id: I4000f32ee8e7c55a711f928a19379b3a80a8446f