msm: ba: Update video input device enumeration

Remove signal status check during enumeration to avoid
any unnecessary polling of device status during bootup.
The single status check is done when device is open for
streaming.

CRs-Fixed: 1092315
Change-Id: I2027fe0fab0fb865071001e7400ba7672433d8f5
Signed-off-by: Shiju Mathew <shijum@codeaurora.org>