ALSA: hda - Make Thinkpad X220-tablet use generic parser

Like the X220, this quirk was added to support docking station,
so enable the fixup instead.

According to Jan, the generic parser works equal or better
than the current parser. This was tested under a 3.9 kernel.

Reported-by: Jan Alexander Steffens <jan.steffens@gmail.com>
Signed-off-by: David Henningsson <david.henningsson@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>