The fe_type_t documentation was incomplete and not linked to the
dvb/frontend.h.xml. Properly document it.

Also, drop a note that newer formats are only supported via
FE_GET_PROPERTY/FE_GET_SET_PROPERTY ioctls.
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

With this change, it is now possible to discover the gap between
the API defined inside include/dvb/frontend.h and the one documented
into the specs.
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

This patch addresses several issues pointed by Randy Dunlap
<rdunlap@xenotime.net> at changeset ece722c:

- In the generated index.html file, "media" is listed first, but it
  should be listed in alphabetical order, not first.

- The generated files are (hidden) in .tmpmedia/

- The link from the top-level index.html file to "media" is to
  media/index.html, but the file is actually in .tmpmedia/media/index.html

- Please build docs with and without using "O=builddir" and test that.

- Would it be possible for media to have its own Makefile instead of
  merging into this one?

Due to the way cleandocs target works, I had to rename the media DocBook
to media_api, otherwise cleandocs would remove the /media directory.

Thanks-to: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>