Port nRF54L15 to the s145 SoftDevice Arduino core (#11842)

* Remove the Zephyr based nRF54L15 port

* Add nRF54L15 port on the s145 Arduino core: nrf54l15dk and xiao_nrf54l15 variants

* nRF54L: errno-style nrfx results, flush console before assert reset

* nRF54L: log the SoftDevice status on Bluefruit failure, ignore the seed request event

* Support the Wio-LR2021 LoRa Plus expansion board with OLED and K1 on the XIAO nRF54L15 variant

* Consume the nRF54L15 platform, core and bootloader from their repositories

* Pin the nRF54L15 platform to v0.2.0

* nRF52: forward SoftDevice flash events taken by the main loop to the flash driver, log the pairing failure status

* Pin the nRF54L15 platform to v0.2.1

* Pin the nRF54L15 platform to v0.3.0

* Split the XIAO nRF54L15 variant into SX1262 and LoRa Plus environments, seed the SoftDevice on request, add the nrf54l15 CI build script

* Pin the nRF54L15 platform to meshtastic/platform-nordicnrf54 v0.3.1

* NRF54: Fix mtjson generation

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Co-authored-by: vidplace7 <vidplace7@gmail.com>

src/modules/AdminModule.cpp

@@ -1819,10 +1819,6 @@ void AdminModule::handleGetDeviceConnectionStatus(const meshtastic_MeshPacket &r
     if (config.bluetooth.enabled && nrf52Bluetooth) {
         conn.bluetooth.is_connected = nrf52Bluetooth->isConnected();
     }
-#elif defined(ARCH_NRF54L15)
-    if (config.bluetooth.enabled && nrf54l15Bluetooth) {
-        conn.bluetooth.is_connected = nrf54l15Bluetooth->isConnected();
-    }
 #endif
 #endif
     conn.has_serial = true; // No serial-less devices
@@ -2512,9 +2508,6 @@ void disableBluetooth()
 #elif defined(ARCH_NRF52)
     if (nrf52Bluetooth)
         nrf52Bluetooth->shutdown();
-#elif defined(ARCH_NRF54L15)
-    if (nrf54l15Bluetooth)
-        nrf54l15Bluetooth->shutdown();
 #endif
 #endif
 }