Revert "Make route_compare() globally defined."

This reverts commit 9edf0a14.

route.c

@@ -56,10 +56,10 @@ static int two_to_the_one_over_hl = 0; /* 2^(1/hl) * 0x10000 */
    contains a linked list of the routes to this prefix, with the
    installed route, if any, at the head of the list. */
 
-int
+static int
 route_compare(const unsigned char *prefix, unsigned char plen,
               const unsigned char *src_prefix, unsigned char src_plen,
-              const struct babel_route *route)
+              struct babel_route *route)
 {
     int i = memcmp(prefix, route->src->prefix, 16);
     if(i != 0)

route.h

@@ -69,9 +69,6 @@ route_metric_noninterfering(const struct babel_route *route)
     return MIN(m, INFINITY);
 }
 
-int route_compare(const unsigned char *prefix, unsigned char plen,
-                  const unsigned char *src_prefix, unsigned char src_plen,
-                  const struct babel_route *route);
 struct babel_route *find_route(const unsigned char *prefix, unsigned char plen,
                         const unsigned char *src_prefix, unsigned char src_plen,
                         struct neighbour *neigh, const unsigned char *nexthop);