ARM: dts: msm: Update context bank lable of VFE for 8916

Camera client side driver has been updated and
now uses 'vfe' instead of 'vfe0' as context bank
label. Propogate the corresponding change to
device tree entry.

Change-Id: I5f26acf78422d704acc85cc9ea90fda1be84e2b0
Signed-off-by: Susheel Khiani <skhiani@codeaurora.org>