Update FreeBSD revision of RTEMS <sys/bitset.h>

Signed-off-by: Sebastian Huber <sebastian.huber@embedded-brains.de>

newlib/libc/sys/rtems/include/sys/bitset.h

@@ -26,7 +26,7 @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
- * $FreeBSD: head/sys/sys/bitset.h 299184 2016-05-06 16:41:23Z royger $
+ * $FreeBSD: head/sys/sys/bitset.h 318781 2017-05-24 10:09:54Z kib $
  */
 
 #ifndef _SYS_BITSET_H_