defconfig: msm8909-1gb: Enable kernel configs for VPN support

Enabling kernel configs for supporting VPN in 8909
- Enabling configs only for 8909-1gb since vpn config
  changes for 8909 512mb variant are already present
- Few configs are already present in 8909-1gb perf,
  so adding only the remaining ones

CRs-Fixed: 797404
Change-Id: Ifcaa3538b4d55f6e82a899ecbc319d4fb7fa60fb
Signed-off-by: Ravinder Konka <rkonka@codeaurora.org>