### Description
The Mbed 2 release was broken for FF_LPC546XX as it would include
the entire mbed 2 build of the LPC546XX. This PR seperates these 2
builds completely by:
* Removing non-shared extra labels from the MCU_LPC546XX target
* Moving the target implementation to a shared target directory
### Pull request type
[x] Fix
[ ] Refactor
[ ] Target update
[ ] Functionality change
[ ] Breaking change
This also includes their Datagram counterparts: DTLSSocket and DTLSSocketWrapper.
Coverage missing for timer-related functionality, but this would require more advanced stub development.
The extra (d)tls_test_config.h is necessary for successful compilation without HW support for the mbedtls features in unittests.
I reused the mbedtls stub found in features/nanostack/coap-service/test/coap-service/unittest/stub/mbedtls_stub.c and amended it slightly with a few missing functions.
DTLSSocketWrapper is equivalent of TLSSocketWrapper but uses datagram mode
and timers for handling Mbed TLS timeouts.
Non-blocking connections were not working earlier, now fixed for both
secure socket modes.
Updated cellular debug trace prints:
- Removed unnecessary prints.
- Tracing more in DEBUG level.
- Read/write bytes not printed on big packets.
- Signal quality (RSSI) traced to log network problems.
- Dismissed AT data is traced.
- Modem type and firmware version are traced.
Network registration returns NotRegistered instead of StatusNotAvailable,
because that's not in 3GPP TS 27.007.
Added smarter rounding of times in recv_timeout and increased the delta by one, to allow "off-by-one" errors.
Reverted commit 88eea6a, reducing TESTS_TIMEOUT back to 480.
Introduced a 100ms timeout for waiting on asynchronous DNS resolution.
Improved error handling on disconnects.
Busy-wait before sending a charecter instead of after. If
serial_writeable has been called first, the busy-wait loop will
be skipped.
Added initialization code to ensure NRF_UARTE_EVENT_TXDRDY is
armed correctly.
In nordic_nrf5_uart_event_handler if the events NRF_UARTE_EVENT_ENDRX
and NRF_UARTE_EVENT_RXSTARTED become pending after the check for
NRF_UARTE_EVENT_ENDRX but before the check for
NRF_UARTE_EVENT_RXSTARTED the RX DMA buffers will be setup incorrectly
by nordic_nrf5_uart_event_handler_rxstarted because active_bank hasn't
been updated. This cause dropped and incorrect data.
This patch fixes that problem by adding a second check for
NRF_UARTE_EVENT_ENDRX after checking for NRF_UARTE_EVENT_RXSTARTED
and skipping processing if NRF_UARTE_EVENT_ENDRX is set. The
subsequent interrupt will process both in the correct order. This
ensures that these events cannot be handled out of order and thus fixes
the corruption.