msm: camera: cci: Avoid reading from i2c fifo if empty

Avoid reading from cci i2c read buffer while register dump, This may
lead to read underflow status bits getting set.

CRs-Fixed: 2662669
Change-Id: I6035af21277ab291e536c91ba08a1f054a59f923
Signed-off-by: Tony Lijo Jose <tjose@codeaurora.org>