Tinyalsa: Add support to poll on alsa control

ALSA controls support polling on the kcontrols, this is used in HD-A for
jack notifcation. In tinyalsa we can use this for notfication from sound
card for any events detected by DSP

Upstream:
https://github.com/tinyalsa/tinyalsa/pull/93
https://github.com/tinyalsa/tinyalsa/pull/94



Change-Id: I4193809bfcdb60f4dc11e1c2ad6a07b29cfa80e9
Signed-off-by: Hardik T Shah <hardik.t.shah@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com>