Enable NanoPC T6 LTS support

Enable NanoPC T6 LTS support

NanoPC T6 board is updated revision to NanoPC T6 LTS.

This patch add NanoPC T6 LTS board support.
  Change asound.state
  Uprev meta-rockchip-extra.

Bug-AGL: SPEC-5276

Change-Id: I0d886122b6ad242afa3cc31ed30a2831d8fe42ea
Signed-off-by: Naoto Yamaguchi <naoto.yamaguchi@aisin.co.jp>
Reviewed-on: https://gerrit.automotivelinux.org/gerrit/c/AGL/meta-agl/+/30507
Reviewed-by: Jan-Simon Moeller <jsmoeller@linuxfoundation.org>
Tested-by: Jan-Simon Moeller <jsmoeller@linuxfoundation.org>