msm: ais: Remove the active_req_cnt < 2 limitation

For multiple camera case, ife irq will be delayed, so
it is easy to make active_req_cnt > = 2, which will reject
the current request and don't send the SOF notification.
We have implemented another mechanism to handle this.

Change-Id: I061ef93222a6a3afd9b1ad020ddbf186dc50618a
Signed-off-by: YUE CHEN <yueche@codeaurora.org>