sys/trickle: Remove xtimer and only use ztimer

sys/Makefile.dep

@@ -225,12 +225,7 @@ endif
 
 ifneq (,$(filter trickle,$(USEMODULE)))
   USEMODULE += random
-  ifeq (,$(filter ztimer_msec,$(USEMODULE)))
-    USEMODULE += xtimer
-    ifneq (,$(filter ztimer_xtimer_compat,$(USEMODULE)))
-      USEMODULE += ztimer_msec
-    endif
-  endif
+  USEMODULE += ztimer_msec
 endif
 
 ifneq (,$(filter eui_provider,$(USEMODULE)))

sys/include/trickle.h

@@ -33,11 +33,7 @@
 #endif
 
 #include "thread.h"
-#if IS_USED(MODULE_ZTIMER_MSEC)
 #include "ztimer.h"
-#else
-#include "xtimer.h"
-#endif
 
 /**
  * @brief Trickle callback function with arguments
@@ -63,13 +59,8 @@ typedef struct {
     trickle_callback_t callback;    /**< callback function and parameter that
                                          trickle calls after each interval */
     msg_t msg;                      /**< the msg_t to use for intervals */
-#if IS_USED(MODULE_ZTIMER_MSEC)
     ztimer_t msg_timer;             /**< timer to send a msg_t to the target
                                          thread for a new interval */
-#else
-    xtimer_t msg_timer;             /**< xtimer to send a msg_t to the target
-                                         thread for a new interval */
-#endif
 } trickle_t;
 
 /**

sys/trickle/trickle.c

@@ -19,6 +19,7 @@
 #include "inttypes.h"
 #include "random.h"
 #include "trickle.h"
+#include "ztimer.h"
 
 #define ENABLE_DEBUG 0
 #include "debug.h"
@@ -53,14 +54,8 @@ void trickle_interval(trickle_t *trickle)
     /* old_interval == trickle->I / 2 */
     trickle->t = random_uint32_range(old_interval, trickle->I);
 
-#if IS_USED(MODULE_ZTIMER_MSEC)
     ztimer_set_msg(ZTIMER_MSEC, &trickle->msg_timer, (trickle->t + diff),
                    &trickle->msg, trickle->pid);
-#else
-    uint64_t msg_time = (trickle->t + diff) * US_PER_MS;
-    xtimer_set_msg64(&trickle->msg_timer, msg_time, &trickle->msg,
-                     trickle->pid);
-#endif
 }
 
 void trickle_reset_timer(trickle_t *trickle)
@@ -93,11 +88,7 @@ void trickle_start(kernel_pid_t pid, trickle_t *trickle, uint16_t msg_type,
 
 void trickle_stop(trickle_t *trickle)
 {
-#if IS_USED(MODULE_ZTIMER_MSEC)
     ztimer_remove(ZTIMER_MSEC, &trickle->msg_timer);
-#else
-    xtimer_remove(&trickle->msg_timer);
-#endif
 }
 
 void trickle_increment_counter(trickle_t *trickle)