Mention zip_file_set_encryption in libzip(3).

man/libzip.mdoc

diff --git a/man/libzip.mdoc b/man/libzip.mdoc
index 2c64f08..ee630e5 100644
--- a/man/libzip.mdoc
+++ b/man/libzip.mdoc
@@ -29,7 +29,7 @@
 .\" OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
 .\" IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 .\"
-.Dd October 1, 2016
+.Dd December 18, 2016
 .Dt LIBZIP 3
 .Os
 .Sh NAME
@@ -98,6 +98,7 @@
 .Xr zip_file_add 3
 .Xr zip_file_replace 3
 .Xr zip_file_set_comment 3
+.Xr zip_file_set_encryption 3
 .Xr zip_set_file_compression 3
 .Xr zip_source_buffer 3
 .Xr zip_source_file 3