free(9) sizes for hooks

[Martin Pieuchot]

Trivial sizes, ok?

Index: net/if.c
===================================================================
RCS file: /cvs/src/sys/net/if.c,v
retrieving revision 1.567
diff -u -p -r1.567 if.c
--- net/if.c    12 Nov 2018 23:41:22 -0000      1.567
+++ net/if.c    28 Nov 2018 20:57:21 -0000
@@ -1088,9 +1088,9 @@ if_detach(struct ifnet *ifp)
                }
        }
 
-       free(ifp->if_addrhooks, M_TEMP, 0);
-       free(ifp->if_linkstatehooks, M_TEMP, 0);
-       free(ifp->if_detachhooks, M_TEMP, 0);
+       free(ifp->if_addrhooks, M_TEMP, sizeof(*ifp->if_addrhooks));
+       free(ifp->if_linkstatehooks, M_TEMP, sizeof(*ifp->if_linkstatehooks));
+       free(ifp->if_detachhooks, M_TEMP, sizeof(*ifp->if_detachhooks));
 
        for (i = 0; (dp = domains[i]) != NULL; i++) {
                if (dp->dom_ifdetach && ifp->if_afdata[dp->dom_family])