Remove support for inherit filters.

It doesn't appear to be useful, and complicates uselessly complicates matters.

filter.c

@@ -240,8 +240,6 @@ parse_filter(gnc_t gnc, void *closure)
             if(metric <= 0 || metric > INFINITY)
                 goto error;
             filter->result = metric;
-        } else if(strcmp(token, "inherit") == 0) {
-            filter->result = METRIC_INHERIT;
         } else {
             goto error;
         }
@@ -453,7 +451,7 @@ input_filter(const unsigned char *id,
 {
     int res;
     res = do_filter(input_filters, id, prefix, plen, neigh, ifindex, 0);
-    if(res < 0 || res == METRIC_INHERIT)
+    if(res < 0)
         res = 0;
     return res;
 }
@@ -464,7 +462,7 @@ output_filter(const unsigned char *id, const unsigned char *prefix,
 {
     int res;
     res = do_filter(output_filters, id, prefix, plen, NULL, ifindex, 0);
-    if(res < 0 || res == METRIC_INHERIT)
+    if(res < 0)
         res = 0;
     return res;
 }

filter.h

@@ -20,8 +20,6 @@ OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 THE SOFTWARE.
 */
 
-#define METRIC_INHERIT (INFINITY + 1)
-
 struct filter {
     int af;
     char *ifname;

xroute.c

@@ -162,8 +162,7 @@ check_xroutes(int send_updates)
         export = 0;
         metric = redistribute_filter(xroutes[i].prefix, xroutes[i].plen,
                                      xroutes[i].ifindex, xroutes[i].proto);
-        if((metric < INFINITY && metric == xroutes[i].metric) ||
-           metric == METRIC_INHERIT) {
+        if(metric < INFINITY && metric == xroutes[i].metric) {
             for(j = 0; j < numroutes; j++) {
                 if(xroutes[i].plen == routes[j].plen &&
                    memcmp(xroutes[i].prefix, routes[j].prefix, 16) == 0 &&
@@ -172,10 +171,6 @@ check_xroutes(int send_updates)
                     if(metric < INFINITY) {
                         export = 1;
                         break;
-                    } else if(metric == METRIC_INHERIT &&
-                              xroutes[i].metric == routes[j].metric * 256) {
-                        export = 1;
-                        break;
                     }
                 }
             }
@@ -207,8 +202,6 @@ check_xroutes(int send_updates)
             continue;
         metric = redistribute_filter(routes[i].prefix, routes[i].plen,
                                      routes[i].ifindex, routes[i].proto);
-        if(metric == METRIC_INHERIT)
-            metric = routes[i].metric * 256;
         if(metric < INFINITY) {
             rc = add_xroute(routes[i].prefix, routes[i].plen,
                             metric, routes[i].ifindex, routes[i].proto);