doc: Fix overfull hboxes errors that cause PDF build to return fail

* overfull hboxes cause texi2dvi to return fail, even if the PDf is written.
  We hacked around this by running it with '...  || true', but that
  sucks for buildboting the docs.

  Fix all the overfull hboxes.

* ospfd.texi: Long command definitions can cause hbox overruns in the
  columnar command definitions index.  This leads to strange errors
  about "Missing number, treated as zero." when building the index -
  very hard to figure out.

  'show ip ospf database ...' was the culprit.  Use a distinct deffnx
  alias for each option instead of trying to stuff them into 1 line.
4 files changed