Remove OSTimer (#4373)

This code is not included anywhere, and none of the functions are
called by code elsewhere in meshtastic.

src/OSTimer.cpp

@@ -1,60 +0,0 @@
-#include "OSTimer.h"
-#include "configuration.h"
-
-/**
- * Schedule a callback to run.  The callback must _not_ block, though it is called from regular thread level (not ISR)
- *
- * NOTE! xTimerPend... seems to ignore the time passed in on ESP32 and on NRF52
- * The reason this didn't work is because xTimerPednFunctCall really isn't a timer function at all - it just means run the
-callback
- * from the timer thread the next time you have spare cycles.
- *
- * @return true if successful, false if the timer fifo is too full.
-
-bool scheduleOSCallback(PendableFunction callback, void *param1, uint32_t param2, uint32_t delayMsec)
-{
-    return xTimerPendFunctionCall(callback, param1, param2, pdMS_TO_TICKS(delayMsec));
-} */
-
-#ifdef ARCH_ESP32
-
-// Super skanky quick hack to use hardware timers of the ESP32
-static hw_timer_t *timer;
-static PendableFunction tCallback;
-static void *tParam1;
-static uint32_t tParam2;
-
-static void IRAM_ATTR onTimer()
-{
-    (*tCallback)(tParam1, tParam2);
-}
-
-/**
- * Schedules a hardware callback function to be executed after a specified delay.
- *
- * @param callback The function to be executed.
- * @param param1 The first parameter to be passed to the function.
- * @param param2 The second parameter to be passed to the function.
- * @param delayMsec The delay time in milliseconds before the function is executed.
- *
- * @return True if the function was successfully scheduled, false otherwise.
- */
-bool scheduleHWCallback(PendableFunction callback, void *param1, uint32_t param2, uint32_t delayMsec)
-{
-    if (!timer) {
-        timer = timerBegin(0, 80, true); // one usec per tick (main clock is 80MhZ on ESP32)
-        assert(timer);
-        timerAttachInterrupt(timer, &onTimer, true);
-    }
-
-    tCallback = callback;
-    tParam1 = param1;
-    tParam2 = param2;
-
-    timerAlarmWrite(timer, delayMsec * 1000UL, false); // Do not reload, we want it to be a single shot timer
-    timerRestart(timer);
-    timerAlarmEnable(timer);
-    return true;
-}
-
-#endif

src/OSTimer.h

@@ -1,8 +0,0 @@
-#pragma once
-
-#include <Arduino.h>
-
-typedef void (*PendableFunction)(void *pvParameter1, uint32_t ulParameter2);
-
-/// Uses a hardware timer, but calls the handler in _interrupt_ context
-bool scheduleHWCallback(PendableFunction callback, void *param1, uint32_t param2, uint32_t delayMsec);