Integrate meta-seconorth-distro/set_default_audio-card_mx6

Commit: seco-ne/yocto/layers/meta-seconorth-distro@b3c8ca1b

alsa:imx6: Switch to sgtl5000 as default audio card

Replaced absolute card number by the ID of the sgtl5000 audio card. Added additional alsa configuration files for imx6ull as it does not have the sgtl5000 codec.

BCS 746-000548