CLOUDSTACK-6075: Increase the ram size for router service offering

Signed-off-by: Rohit Yadav <rohit.yadav@shapeblue.com>
(cherry picked from commit 488c17858f17f548d907cd72df54e0abdfd439b2)
Signed-off-by: Rohit Yadav <rohit.yadav@shapeblue.com>