potential NULL pointer dereference in ifconfig.c

[Remco]

I think there is a potential NULL pointer dereference in ifconfig.c.
(I'm not aware of this causing actual problems, I just spotted it by accident)

Index: ifconfig.c
===================================================================
RCS file: /cvs/src/sbin/ifconfig/ifconfig.c,v
retrieving revision 1.281
diff -u -r1.281 ifconfig.c
--- ifconfig.c  21 Jan 2014 21:27:14 -0000      1.281
+++ ifconfig.c  5 Mar 2014 14:32:24 -0000
@@ -3018,7 +3018,7 @@
 void
 setifprefixlen(const char *addr, int d)
 {
-       if (*afp->af_getprefix)
+       if (afp->af_getprefix)
                (*afp->af_getprefix)(addr, MASK);
        explicit_prefix = 1;
 }