msm: camera: isp: Check open count and VFE_HW state

If the initialization was not successful for csid_hw, then the
open count can be zero and we might end up decrementing the
same. This can cause unbalanced call to disable functions and
excessive logs. Prevent this by adding a check for open count.
Further, add vfe hardware state check before updating bandwidth
and clocks to avoid the same in vfe_start and vfe_stop.

Change-Id: I9ffc3f22ac0cb0dbdd8b171f86f9705306db0b3d
Signed-off-by: Abhilash Kumar <krabhi@codeaurora.org>