uClibc compatibility (#5270)

* uclibc compatibility

Adds compatibility with uclibc, the officially supported toolchain of the luckfox pico

* Explicitly link stdc++fs for std::filesystem

Bringing this over from buildroot-meshtastic

src/mesh/StreamAPI.h

@@ -3,6 +3,7 @@
 #include "PhoneAPI.h"
 #include "Stream.h"
 #include "concurrency/OSThread.h"
+#include <cstdarg>
 
 // A To/FromRadio packet + our 32 bit header
 #define MAX_STREAM_BUF_SIZE (MAX_TO_FROM_RADIO_SIZE + sizeof(uint32_t))

src/modules/PositionModule.cpp

@@ -16,10 +16,7 @@
 #include "meshtastic/atak.pb.h"
 #include "sleep.h"
 #include "target_specific.h"
-
-extern "C" {
 #include <Throttle.h>
-}
 
 PositionModule *positionModule;