ALSA: hda - Add mic fixup for Gigabyte BXBT-2807

The Gigabyte BRIX BXBT-2707 is a mini-PC with Realtek ALC283 HDA,
exposing a single headset jack.

However, the default pin config information only suggests
that one pin is connected: a HP out jack (pin 0x21, default
config 0x04211010).

The microphone input is behind pin 0x19, which has default
config 0x411111f0 (i.e. unused), so it does not show up in
userspace, and no microphone input is possible via the headset.

Override the pin config so that the headset mic can be used.

[rearranged the fixup entry position by tiwai]

Signed-off-by: Daniel Drake <drake@endlessm.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Merge pull request #4 from endlessm/shell/2932

ALSA: hda - Add mic fixup for Gigabyte BXBT-2807