ath10k: support get/set antenna configurations.

Tested with CT firmware, but should work on standard
firmware as well.

Verified that target's tx/rx chain register is set appropriately,
and that the tx rate goes down as number of chains
decrease, but I did not actually try to verify antenna
ceased to transmit when disabled.

Change-Id: Ie3985a59233ddb793801db5cb9228ab838296d26
Signed-off-by: Ben Greear <greearb@candelatech.com>
Tested-by: Avery Pennarun <apenwarr@gmail.com>
3 files changed