schedule: (cosmetic) eliminate repeated code

Remove a repeated line in arch_schedulers_get() and update
arch_user_schedulers_get() to look more like the former.

Signed-off-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>

Author: lyakh

zephyr/schedule.c

@@ -33,13 +33,11 @@ static APP_SYSUSER_BSS struct schedulers *_schedulers_user[CONFIG_CORE_COUNT];
  */
 struct schedulers **arch_schedulers_get(void)
 {
-#ifndef CONFIG_SOF_USERSPACE_LL
-	return _schedulers + cpu_get_id();
-#else
+#ifdef __ZEPHYR__
 	/* user-space use of schedule.h must usearch_user_schedulers_get() */
 	assert(!k_is_user_context());
-	return _schedulers + cpu_get_id();
 #endif
+	return _schedulers + cpu_get_id();
 }
 EXPORT_SYMBOL(arch_schedulers_get);
 
@@ -53,6 +51,7 @@ EXPORT_SYMBOL(arch_schedulers_get);
 struct schedulers **arch_user_schedulers_get(void)
 {
 #ifdef CONFIG_SOF_USERSPACE_LL
+	assert(!k_is_user_context());
 	return _schedulers_user + cpu_get_id();
 #else
 	return NULL;