add support for otter2 (2nd-gen KFire)

Change-Id: I6b85abb3eb0adde54e606c603e30afea37082e47
defconfig: update 1st-gen defconfig

Change-Id: Ieea12bc81b58b3be4fb1ce192421460993c0e8a7
defconfig: add 2nd-gen defconfig

Change-Id: Ibb21554a6e093e4151ea391f740a676bb3f0a898