pthread: move pthread_cond to userspace

Move pthread condition variable implementation from kernel (sched/pthread)
to userspace library (libs/libc/pthread). This allows userspace to handle
condition variable operations directly, reducing syscall overhead and
improving performance for pthread applications.

Signed-off-by: hujun5 <hujun5@xiaomi.com>

libs/libc/semaphore/sem_wait.c

@@ -200,3 +200,75 @@ int nxsem_wait(FAR sem_t *sem)
 
   return nxsem_wait_slow(sem);
 }
+
+/****************************************************************************
+ * Name: nxsem_wait_uninterruptible
+ *
+ * Description:
+ *   This function is wrapped version of nxsem_wait(), which is
+ *   uninterruptible and convenient for use.
+ *
+ * Parameters:
+ *   sem - Semaphore descriptor.
+ *
+ * Return Value:
+ *   Zero(OK)  - On success
+ *   EINVAL    - Invalid attempt to get the semaphore
+ *   ECANCELED - May be returned if the thread is canceled while waiting.
+ *
+ ****************************************************************************/
+
+int nxsem_wait_uninterruptible(FAR sem_t *sem)
+{
+  int ret;
+
+  do
+    {
+      /* Take the semaphore (perhaps waiting) */
+
+      ret = nxsem_wait(sem);
+    }
+  while (ret == -EINTR);
+
+  return ret;
+}
+
+/****************************************************************************
+ * Name: nxsem_clockwait_uninterruptible
+ *
+ * Description:
+ *   This function is wrapped version of nxsem_clockwait(), which is
+ *   uninterruptible and convenient for use.
+ *
+ * Input Parameters:
+ *   sem     - Semaphore object
+ *   clockid - The timing source to use in the conversion
+ *   abstime - The absolute time to wait until a timeout is declared.
+ *
+ * Returned Value:
+ *   EINVAL    The sem argument does not refer to a valid semaphore.  Or the
+ *             thread would have blocked, and the abstime parameter specified
+ *             a nanoseconds field value less than zero or greater than or
+ *             equal to 1000 million.
+ *   ETIMEDOUT The semaphore could not be locked before the specified timeout
+ *             expired.
+ *   EDEADLK   A deadlock condition was detected.
+ *   ECANCELED May be returned if the thread is canceled while waiting.
+ *
+ ****************************************************************************/
+
+int nxsem_clockwait_uninterruptible(FAR sem_t *sem, clockid_t clockid,
+                                    FAR const struct timespec *abstime)
+{
+  int ret;
+
+  do
+    {
+      /* Take the semaphore (perhaps waiting) */
+
+      ret = nxsem_clockwait(sem, clockid, abstime);
+    }
+  while (ret == -EINTR);
+
+  return ret;
+}