disp: msm: dsi: Update ctrl & phy refcounts for defer probe

ctrl and phy refcounts get incremented even on deferring probe
for display panels which need backlight through wled.As a
result, while probing, it considers that the device is already
in use. This change decrements the ctrl and phy refcounts for
defer probe.

Change-Id: Ica1f5712dd28ed4c635946f2ac89d5f4f074a4c5
Signed-off-by: Lipsa Rout <lrout@codeaurora.org>