For codec AD1984A, add a new model to support Dell Precision R5500
or the microphone jack won't work correctly.

BugLink: http://bugs.launchpad.net/bugs/741516Tested-by: NKent Baxley <kent.baxley@canonical.com>
Cc: stable@kernel.org
Signed-off-by: NDavid Henningsson <david.henningsson@canonical.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>