doc: add missing API content

Some API material (from doxygen comments) wasn't included in the
generated documentation because there was no doxygengroup Sphinx
directive to display them. This PR add content into appropriate places
in existing documentation (e.g., Bluetooth Cryptography APIs into the
Bluetooth API doc) and creates two new collections for Display and
Miscellaneous APIs.

Comments added to the .rst files to mention doxygengroups that are
intentionally excluded (because they're organizational groups containing
subgroups that are included).

Sorted the Bluetooth API list, mostly.

Fixed a couple doxygen group titles defined in the include files, and
added a few patterns to filter new "expected" errors from the document
generation process.

Legacy and deprecated APIs remain left out, as intended:

   http_legacy  (net/http_legacy.h)
   spi_interface_legacy  (spi_legacy.h)
   zoap  (net/zoap.h)

fixes: Issue #5051

Signed-off-by: David B. Kinder <david.b.kinder@intel.com>