xtimer: Move xtimer_spin_until into xtimer_core.c

sys/include/xtimer/implementation.h

@@ -106,14 +106,6 @@ static inline uint32_t xtimer_now(void)
 #endif
 }
 
-static inline void xtimer_spin_until(uint32_t target) {
-#if XTIMER_MASK
-    target = _xtimer_lltimer_mask(target);
-#endif
-    while (_xtimer_lltimer_now() > target);
-    while (_xtimer_lltimer_now() < target);
-}
-
 static inline void xtimer_spin(uint32_t offset) {
     uint32_t start = _xtimer_lltimer_now();
 #if XTIMER_MASK

sys/xtimer/xtimer_core.c

@@ -35,6 +35,8 @@ static volatile uint32_t _long_cnt = 0;
 volatile uint32_t _xtimer_high_cnt = 0;
 #endif
 
+static inline void xtimer_spin_until(uint32_t value);
+
 static xtimer_t *timer_list_head = NULL;
 static xtimer_t *overflow_list_head = NULL;
 static xtimer_t *long_list_head = NULL;
@@ -56,6 +58,14 @@ static inline int _is_set(xtimer_t *timer)
     return (timer->target || timer->long_target);
 }
 
+static inline void xtimer_spin_until(uint32_t target) {
+#if XTIMER_MASK
+    target = _xtimer_lltimer_mask(target);
+#endif
+    while (_xtimer_lltimer_now() > target);
+    while (_xtimer_lltimer_now() < target);
+}
+
 void xtimer_init(void)
 {
     /* initialize low-level timer */