dsp: adm: increase the length of timeout in adm_open to 2 seconds

Currently, the length of timeout in adm_open for waiting response
from ADSP is 1 second. To prevent unnecessary timeout that results
adm_open failure, increase the length of timeout to 2 seconds.

Change-Id: I670f44964538c3176130c4bb5f8b7a3b3eaf8d8b
Signed-off-by: Xiaoyu Ye <benyxy@codeaurora.org>