Fix mobile builds

client/internal/routemanager/systemops/systemops_mobile.go

@@ -3,12 +3,9 @@
 package systemops
 
 import (
-	"errors"
 	"net/netip"
 )
 
-var ErrRoutingIsSeparate = errors.New("routing is separate")
-
-func hasSeparateRouting() ([]netip.Prefix, error) {
-	return nil, ErrRoutingIsSeparate
+func IsAddrRouted(addr netip.Addr, vpnRoutes []netip.Prefix) (bool, netip.Prefix) {
+	return false, nil
 }