[qca-nss-ecm] Set correct flow/return MTU in L2TPv2 outer rule

- CRs-Fixed: 951301
- Set flow/return MTU of outer/tunnel rule of L2Tpv2 tunnel such
  that it may service all sessions created within it.

Change-Id: Ic72f1677462caae03dca4f09bf27584db3f58c28
Signed-off-by: Tushar Mathur <tushar@codeaurora.org>
1 file changed