ARM: dts: msm: add bluetooth node and BT_EN for hastings

On kona,
1.) GPIO 21 is used to toggle BT_EN pin, adding BT_EN
in bluetooth node for hastings chip.
2.) AON 0.95V added for AON supply S6A.
3.) Add bt_en_active in pinctrol so as to make BT_EN
pin controllable.

Change-Id: I1c2028d07f7397489c488ed3e2c00d4286c6d6e5
Signed-off-by: Mahesh kumar sharma <smahesh@codeaurora.org>