kernel/poll: add missing poll_event runtime init

It was in the static initializers, but was missing from the object
runtime init functions.

Change-Id: I10d519760eabdbe640a19cc5cfa9241c1356b070
Signed-off-by: Benjamin Walsh <walsh.benj@gmail.com>

include/kernel.h

@@ -3104,6 +3104,12 @@ extern void k_free(void *ptr);
 
 /* polling API - PRIVATE */
 
+#ifdef CONFIG_POLL
+#define _INIT_OBJ_POLL_EVENT(obj) do { (obj)->poll_event = NULL; } while ((0))
+#else
+#define _INIT_OBJ_POLL_EVENT(obj) do { } while ((0))
+#endif
+
 /* private - implementation data created as needed, per-type */
 struct _poller {
 	struct k_thread *thread;

kernel/fifo.c

@@ -52,6 +52,8 @@ void k_fifo_init(struct k_fifo *fifo)
 	sys_slist_init(&fifo->data_q);
 	sys_dlist_init(&fifo->wait_q);
 
+	_INIT_OBJ_POLL_EVENT(fifo);
+
 	SYS_TRACING_OBJ_INIT(k_fifo, fifo);
 }
 

kernel/sem.c

@@ -73,6 +73,9 @@ void k_sem_init(struct k_sem *sem, unsigned int initial_count,
 	sem->count = initial_count;
 	sem->limit = limit;
 	sys_dlist_init(&sem->wait_q);
+
+	_INIT_OBJ_POLL_EVENT(sem);
+
 	SYS_TRACING_OBJ_INIT(k_sem, sem);
 }