sched/semaphore: remove dead code if no CONFIG_PRIORITY_PROTEC

Consolidate CONFIG_PRIORITY_PROTECT checks by moving macro definitions to
their actual usage locations and removing duplicate/dead code in semaphore
implementation. This reduces code duplication and improves maintainability
across sem_wait, sem_trywait, and sem_post functions.

Signed-off-by: p-gaoxiang43 <p-gaoxiang43@xiaomi.com>

sched/semaphore/sem_post.c

@@ -246,7 +246,9 @@ int nxsem_post_slow(FAR sem_t *sem)
         }
       else if (proto == SEM_PRIO_PROTECT)
         {
+#ifdef CONFIG_PRIORITY_PROTECT
           nxsem_protect_post(sem);
+#endif
         }
 
       sched_unlock();

sched/semaphore/sem_trywait.c

@@ -63,7 +63,7 @@
 int nxsem_trywait_slow(FAR sem_t *sem)
 {
   irqstate_t flags;
-  int ret = -EAGAIN;
+  int ret = OK;
   bool mutex = NXSEM_IS_MUTEX(sem);
   FAR atomic_t *val = mutex ? NXSEM_MHOLDER(sem) : NXSEM_COUNT(sem);
   int32_t old;
@@ -103,6 +103,7 @@ int nxsem_trywait_slow(FAR sem_t *sem)
 
   /* It is, let the task take the semaphore */
 
+#ifdef CONFIG_PRIORITY_PROTECT
   ret = nxsem_protect_wait(sem);
   if (ret < 0)
     {
@@ -117,6 +118,7 @@ int nxsem_trywait_slow(FAR sem_t *sem)
 
       goto out;
     }
+#endif
 
   if (!mutex)
     {

sched/semaphore/sem_wait.c

@@ -73,7 +73,7 @@ int nxsem_wait_slow(FAR sem_t *sem)
 {
   FAR struct tcb_s *rtcb = this_task();
   irqstate_t flags;
-  int ret;
+  int ret = OK;
   bool unlocked;
   FAR struct tcb_s *htcb = NULL;
   bool mutex = NXSEM_IS_MUTEX(sem);
@@ -121,6 +121,7 @@ int nxsem_wait_slow(FAR sem_t *sem)
     {
       /* It is, let the task take the semaphore. */
 
+#ifdef CONFIG_PRIORITY_PROTECT
       ret = nxsem_protect_wait(sem);
       if (ret < 0)
         {
@@ -136,6 +137,7 @@ int nxsem_wait_slow(FAR sem_t *sem)
           leave_critical_section(flags);
           return ret;
         }
+#endif
 
       /* For mutexes, we only add the holder to the tasks list at the
        * time when a task blocks on the mutex, for priority restoration

sched/semaphore/semaphore.h

@@ -102,9 +102,6 @@ void nxsem_release_all(FAR struct tcb_s *stcb);
 #ifdef CONFIG_PRIORITY_PROTECT
 int nxsem_protect_wait(FAR sem_t *sem);
 void nxsem_protect_post(FAR sem_t *sem);
-#else
-#  define nxsem_protect_wait(sem)  0
-#  define nxsem_protect_post(sem)
 #endif
 
 #undef EXTERN