Experiment: C++17 support (#9874)

* Add C++17 support

* Add C++17 runtime probes and update build configurations for STM32 and Portduino

* Remove unflags

* Update C++ standard flags across the platforms

* Convert a couple of instances to structured bindings

* NRF52 platform.txt to add C++17 support

* Still need the unflags apparently

* Remove C++17 runtime probe tests from test_main.cpp

* Reconfigured doesnt need a nodiscard

* Remove nodiscard attribute from init() method in RadioInterface

* Remove mbedtls/error.h from build flags

Removed include directive for mbedtls/error.h from build flags.

* Fix IRAM overflow

* Fix IRAM overflow

* Add build flag to exclude MQTT from rak11200

* Update C++ standard from gnu17 to gnu++17

variants/nrf52840/nrf52.ini

@@ -5,9 +5,9 @@ platform =
   platformio/nordicnrf52@10.11.0
 extends = arduino_base
 platform_packages =
-  ; our custom Git version until they merge our PR
+  ; our custom Git version with C++17 support in platform.txt
   # TODO renovate
-  platformio/framework-arduinoadafruitnrf52 @ https://github.com/meshtastic/Adafruit_nRF52_Arduino#74096746e5f167a2ff22e483d8e79bb1aef00591
+  platformio/framework-arduinoadafruitnrf52 @ https://github.com/meshtastic/Adafruit_nRF52_Arduino#cpp17-platform
   ; Don't renovate toolchain-gccarmnoneeabi
   platformio/toolchain-gccarmnoneeabi@~1.90301.0
 
@@ -35,6 +35,8 @@ build_unflags =
   -g
   -g1
   -g0
+  -std=c++11
+  -std=gnu++11
 
 build_src_filter = 
   ${arduino_base.build_src_filter} -<platform/esp32/> -<platform/stm32wl> -<nimble/> -<mesh/wifi/> -<mesh/api/> -<mesh/http/> -<modules/esp32> -<platform/rp2xx0> -<mesh/eth/> -<mesh/raspihttp> -<serialization/>