I can not find anywhere we use the logo-*.png files currently in the
gitea public directory. Remove these as they're all trivially
re-created via the SVG if we find we want them.
Similarly I don't see anywhere we use "opendev-icon.svg"; it is the
same as "logo.svg". This is removed.
Move the logo with text "opendev.svg" into the assets bundle (only
user of this I can find is paste.opendev.org).
Also move in the favicon.<png/svg> files
Note all these are copied back into the gitea container at the same
location so nothing will break. However we wish to have the
identified external users not rely on files served as gitea assets as
the new version of gitea will move them.
Change-Id: I4f6c64b4042a3f0a17ce4ee59ee8bd0d61648bcc