QThread/Unix: move qt_nanosleep to qthread_unix.cpp

It's the only place that uses it.

Pick-to: 6.5
Change-Id: Ieec322d73c1e40ad95c8fffd17465370ac209c2f
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>
Reviewed-by: Ahmad Samir <a.samirh78@gmail.com>

src/corelib/kernel/qcore_unix_p.h

@@ -373,7 +373,6 @@ static inline pid_t qt_safe_waitpid(pid_t pid, int *status, int options)
 
 // in qelapsedtimer_mac.cpp or qtimestamp_unix.cpp
 timespec qt_gettime() noexcept;
-void qt_nanosleep(timespec amount);
 QByteArray qt_readlink(const char *path);
 
 /* non-static */

src/corelib/kernel/qelapsedtimer_unix.cpp

@@ -139,20 +139,6 @@ struct timespec qt_gettime() noexcept
     return tv;
 }
 
-void qt_nanosleep(timespec amount)
-{
-    // We'd like to use clock_nanosleep.
-    //
-    // But clock_nanosleep is from POSIX.1-2001 and both are *not*
-    // affected by clock changes when using relative sleeps, even for
-    // CLOCK_REALTIME.
-    //
-    // nanosleep is POSIX.1-1993
-
-    int r;
-    EINTR_LOOP(r, nanosleep(&amount, &amount));
-}
-
 static qint64 elapsedAndRestart(qint64 sec, qint64 frac,
                                 qint64 *nowsec, qint64 *nowfrac)
 {

src/corelib/thread/qthread_unix.cpp

@@ -491,6 +491,20 @@ void QThread::yieldCurrentThread()
 
 #endif // QT_CONFIG(thread)
 
+static void qt_nanosleep(timespec amount)
+{
+    // We'd like to use clock_nanosleep.
+    //
+    // But clock_nanosleep is from POSIX.1-2001 and both are *not*
+    // affected by clock changes when using relative sleeps, even for
+    // CLOCK_REALTIME.
+    //
+    // nanosleep is POSIX.1-1993
+
+    int r;
+    EINTR_LOOP(r, nanosleep(&amount, &amount));
+}
+
 void QThread::sleep(unsigned long secs)
 {
     qt_nanosleep(durationToTimespec(std::chrono::seconds{secs}));