Fixed headset detection broken on stingray

commit 5e64321e broke the headset detection on stingray.
This is because the name passed with the UEvent upon headset insertion/removal is
different from the dev path (h2w). It actually indicates the type of headset connected.

The fix consists in using the dev path received with the UEvent to find the corresponding
entry in uEventInfo.

Change-Id: I8481cfa17a7af3c8f5d83fc87d0f7c0d2c981098