altq: Remove stale driver references

Remove xr to an(4) and npe(4) since they no longer exist in the tree.

Sponsored by:		Netflix

share/man/man4/altq.4

@@ -23,7 +23,7 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.Dd November 10, 2022
+.Dd January 21, 2024
 .Dt ALTQ 4
 .Os
 .Sh NAME
@@ -128,7 +128,6 @@ They have been applied to the following hardware drivers:
 .Xr age 4 ,
 .Xr alc 4 ,
 .Xr ale 4 ,
-.Xr an 4 ,
 .Xr aue 4 ,
 .Xr axe 4 ,
 .Xr bce 4 ,
@@ -152,7 +151,6 @@ They have been applied to the following hardware drivers:
 .Xr my 4 ,
 .Xr nfe 4 ,
 .Xr nge 4 ,
-.Xr npe 4 ,
 .Xr qlxgb 4 ,
 .Xr re 4 ,
 .Xr rl 4 ,