The 'pthread_condattr_setclock' missing on OpenWrt platform.

thread/qwaitcondition_unix.cpp: In function 'void qt_initialize_pthread_cond(pthread_cond_t*, const char*)': thread/qwaitcondition_unix.cpp:83: error: 'pthread_condattr_setclock' was not declared in this scope

// Android lacks pthread_condattr_setclock, but it does have a nice function
// for relative waits. Use weakref so we can determine at runtime whether it is
// present.

./configure -arch arm -no-c++11 -prefix $(CONFIGURE_PREFIX) \
 -bindir $(CONFIGURE_PREFIX)/bin -libdir $(CONFIGURE_PREFIX)/lib \
 -datadir $(CONFIGURE_PREFIX)/share/Qt -plugindir \
 $(CONFIGURE_PREFIX)/lib/Qt/plugins -xplatform linux-openwrt-g++ \
 -opensource -confirm-license -no-sql-db2 -no-sql-ibase \
 -no-sql-mysql -no-sql-oci -no-sql-odbc -no-sql-psql \
 -no-sql-sqlite -no-sql-sqlite2 -no-sql-tds -no-qml-debug \ -no-gif \
 -no-libpng -no-libjpeg -no-xcb -no-strip -openssl -no-gui \
 -no-widgets -no-nis -no-cups -no-dbus -no-eglfs -no-directfb \
 -no-linuxfb -no-kms -no-opengl -no-javascript-jit -skip qtwebkit \
 -make libs -nomake webkit -nomake docs -nomake examples \
 -nomake demos -nomake tests -nomake script -skip qtdeclarative \
 -skip qtjsbackend -skip qtmultimedia -skip activeqt -skip qtwebkit \
 -skip qtwebkit-examples-and-demos -skip qtimageformats -skip \
 qtgraphicaleffects -skip qtdoc -v