tests/posix_semaphore: private sub functions for tests libs

tests/periph_dma: add automatic testing of DMA over UART

cpu/esp32: fix of buffer sizes and length checking in esp_eth and esp_wifi

boards/stm32: revert forced use of dma feature in STM32 boards

testrunner: fix script when RIOTBASE is not defined

Since complete MAC frames are handled, ETHERNET_MAX_LEN has to be used instead of ETHERNET_DATA_LEN for buffer sizes and length checks.

Since complete MAC frames are handled, ETHERNET_MAX_LEN has to be used instead of ETHERNET_DATA_LEN for buffer sizes and length checks.

The periph_dma is not pulled in automatically for all applications.
Applications willing to use the configured peripherals with periph_dma
for a given board will have to include the feature explictly in their
Makefile.

It was causing unrelated issues as threads got de-scheduled while
calling printf and this was not handled properly in tests at that
moment.

While trying python test libraries, like pytest, the automatic test collection
detects the `testNUM` functions as tests but does not know the `term` argument
and fails.

This declares them as private to only find `testfunc(child)` entry point.

Another solution could have been to use `testNUM(child)` and rename
`testfunc` to `main` but would not match other tests.

If not defined it was raising a KeyError. Use the 'get' function to
handle non defined value.

It did not put the value in the `default` case as it would have changed
the behavior when `RIOTBASE` is defined but empty.

boards/b-l475e-iot01a: provide already configured RTC and RTT features

RTC and RTT are available and already configured for this board but not provided by the build system

cpu/esp32: fixes the memset optimization problem in esp_wifi/wpa_supplicant

nrfmin: fix type for NETOPT_PROTO

Makefile.include: append the values to GLOBAL_GOALS

The type [is documented as `gnrc_nettype_t`][1] so it should by checked
as such.

[1]: https://github.com/RIOT-OS/RIOT/blob/f9a3bdf1a749f0e6a0d9e79eee652d8b31d4d9e0/sys/include/net/netopt.h#L210-L212

net/nanocoap: fix confirmable retry countdown

eui48: fix type alignment

This allows setting other GLOBAL_GOALS by setting it before.
This could be the case for the application `Makefile` or files parsed
from `RIOT_MAKEFILES_GLOBAL_PRE`.

tests/pkg_{hacl,monocypher}: set custom timeout value

tests/periph_rtc: add automatic python test script

tests/periph_flashpage: improve flashpage tests

On samr30-xpro the tests takes respectively 20 and 14 seconds to complete

examples/gcoap: verify buffer size

tests/periph_rtc: fix alarm period in README

The default period value the application code is set to 2s

doc: fix warnings in *_params.h

nrfmin: remove long address support

pkg/nordic_softdevice_ble: Use MAC48 as hardware address

This is just a compatibility issue waiting to happen as soon as there
is support for a more standard-compliant implementation of BLE (like
e.g. NimBLE ;-)).

boards/hifive1: fix file permissions of flasher.sh

cpu/esp32: esp_wifi netdev driver