So far, hda_jack infrastructure allows only one callback per jack, and
this makes things slightly complicated when a driver wants to assign
multiple tasks to a jack, e.g. the standard auto-mute with a power
up/down sequence.  This can be simplified if the hda_jack accepts
multiple callbacks.

This patch is such an extension: the callback-specific part (the
function and private_data) is split to another struct from
hda_jack_tbl, and multiple such objects can be assigned to a single
hda_jack_tbl entry.

The new struct hda_jack_callback is passed to each callback function
now, thus the patch became bigger than expected.  But these changes
are mostly trivial.

Signed-off-by: Takashi Iwai <tiwai@suse.de>