* Start working on fixing doxygen warnings

* Upgrade doxyfile to Doxygen 1.9.1

* Clean up some unmatched groups and add some exclusions

* Fix docs for rtos::ThisThread not showing up

* Fix up KV store docs

* Fix incorrect @files, some more incorrect groups

* Fix lots of broken links

* Start fixing mbedtls groups

* Fix more mbedtls docs

* Fix remaining mbedtls files with missing or incorrect grouping

* Fix a huge amount of PSA docs errors

* Fix a few more mbedtls docs errors

* Fix __cplusplus not defined for docs, clean up call in callback typedef, fix some docs errors

* Fix some broken doc links in HAL headers

* Fix more PSA doc errors

* Fix some doxygen errors in networking code

* Fix lots of network related doc errors

* Try and fix some CI failures

* Use Doxygen Action instead of doxygen in Mbed container to get the right version

* Try removing docs check

* Add first part of doxygen action

* Add next part of doxygen action

* Fix yaml syntax error

* Add in license check fix

* Try using verbose scancode

* Fix some more docs issues, workaround scancode-toolkit#3179

* Clean up the LoRaRadio get_state() function on each implementation.  Also fix some other compile and doc errors.

* Fix all remaining doxygen errors

* Fix escaping, for realsies this time

* Remove Doxygen unsupported config options, fix some more get_status() declarations

* Fix some UNITTESTS build errors

* Fix one more compile error

* Another unittest error

Some of the lines in `platform_mbed.h` only have `FEATURE_PSA`
checked, which is always set for Mbed OS PSA targets but the PSA
APIs are not actually available unless `FEATURE_EXPERIMENTAL_API`
is also enabled. To fix this and improve readability, group all
PSA-related lines and check both macros.

The compiler gave redefinition warnings if
MBEDTLS_ENTROPY_HARDWARE_ALT is defined in the the compile
definitions. A check is added to prevent this warning.

Don't attempt to use default_random_seed unless both PSA and Experimental API
support are enabled. This prevents errors when the Mbed TLS NV Seed feature is
being used on platforms that have PSA enabled by default, but not Experimental
API support by default.

    [DEBUG] Output: compilation terminated.
    [ERROR] In file included from ./mbed-os/connectivity/mbedtls/include/mbedtls/config.h:31,
                     from ./mbed-os/connectivity/mbedtls/include/mbedtls/entropy.h:28,
    ./mbed-os/connectivity/mbedtls/platform/inc/platform_mbed.h:26:10: fatal error: default_random_seed.h: No such file or directory
       26 | #include "default_random_seed.h"