Audio: headset: add debug board detection mechanism.

1.Use gpio-85: low = debug board and high = no debug board.
2.Only support hardware revison A and after.

Change-Id: If4db1fd8f94036dfb7428e63e54b4ae41b60e0cd
Signed-off-by: sam_chen <sam_chen@asus.com>
1 file changed