Revert "bcmdhd: reenable IPv6, disable multicast in suspend"

This reverts commit 5cf978b2c6493c17a2cef83d5ff609050d89d52c.
Revert "bcmdhd: disable GAN_LITE_NAT_KEEPALIVE_FILTER"

This reverts commit 38617c90da083e79637bf90d1a55141df1e5cf4a.