[kde-base/khelpcenter] Add missing dependency.

Package-Manager: portage-2.2.8-r1
[kde-frameworks/kded] kinit is actually a runtime dependency too.

Note that there are no library links, but rather the binaries
it provides are used. See kinit docs for more information.

Package-Manager: portage-2.2.8-r1
[kde-frameworks/kded] Remove unused USE flag from metadata.

Package-Manager: portage-2.2.8-r1