defconfig: Enable TUN driver support

Enable TUN driver support required in Android VPN service.

CRs-Fixed: 365877
Change-Id: Ib7ccd4328441c6bfa6709f9f2e26ad2994856a18
Signed-off-by: Praveena Pachipulusu <pveena@codeaurora.org>
diff --git a/arch/arm/configs/msm8960_defconfig b/arch/arm/configs/msm8960_defconfig
index 8f576d7..a0636f9 100644
--- a/arch/arm/configs/msm8960_defconfig
+++ b/arch/arm/configs/msm8960_defconfig
@@ -261,6 +261,7 @@
 CONFIG_DM_CRYPT=y
 CONFIG_NETDEVICES=y
 CONFIG_DUMMY=y
+CONFIG_TUN=y
 CONFIG_KS8851=m
 # CONFIG_MSM_RMNET is not set
 CONFIG_MSM_RMNET_BAM=y