repositories: drop lto-overlay

No commits since December 2022, and its use currently prevent
installing anything due to bug #916287 which been ignored upstream
for months following a deprecation period.

Note that Gentoo is mostly handling LTO nowadays, and using a simple
e.g. "-march=native -O2 -flto" for *FLAGS will typically work without
needing an overlay to handle exceptions (if not, please file bugs).

-O3 is fine too, however some other flags (e.g. -fno-plt, -fipa-pta)
may be far more volatile and are not recommended either way.

Not closing bug #916287 for now to make it easier for users to find it.

Bug: https://bugs.gentoo.org/916287
Signed-off-by: Ionen Wolkens <[email protected]>

files/overlays/repositories.xml

@@ -2408,18 +2408,6 @@
  <source type="git">git+ssh:https://[email protected]/xen0n/loongson-overlay.git</source>
  <feed>https://github.com/xen0n/loongson-overlay/commits/master.atom</feed>
  </repo>
- <repo quality="experimental" status="unofficial">
- <name>lto-overlay</name>
- <description lang="en">A Portage configuration for O3, Graphite, and LTO system-wide</description>
- <homepage>https://github.com/InBetweenNames/gentooLTO</homepage>
- <owner type="person">
- <email>[email protected]</email>
- <name>Shane Peelar</name>
- </owner>
- <source type="git">https://github.com/InBetweenNames/gentooLTO.git</source>
- <source type="git">git+ssh:https://[email protected]/InBetweenNames/gentooLTO.git</source>
- <feed>https://github.com/InBetweenNames/gentooLTO/commits/master.atom</feed>
- </repo>
  <repo quality="experimental" status="unofficial">
  <name>luke-jr</name>
  <description>Misc ebuilds by Luke-Jr</description>