cnf/repo.postsync.d/example: add egencache --update-pkg-desc-index (bug 735626)

Add an egencache --update-pkg-desc-index example for users
of app-portage/esearch to migrate to.

Bug: https://bugs.gentoo.org/735626
Reviewed-by: Brian Dolbec <dolsen@gentoo.org>
Signed-off-by: Zac Medico <zmedico@gentoo.org>
1 file changed