msm: mdss: print error code when file node allocation fails

Print error code when file node allocation fails within
fence acquire logic. This helps to find the root cause
for file node allocation failure.

Change-Id: Ib6adb9f612f13cb56d8f43549722b78440f689f8
Signed-off-by: Dhaval Patel <pdhaval@codeaurora.org>