fbdev: msm: Correct ion sequence for splash and pan display

Make changes as per ion call sequence shared by memory team.
dma buf get is not required after dma buf allocation. If not,
put has to be done twice. So remove the redundant get buf
and get fd calls.

Change-Id: I4a521815a9bf75cb12d399a5643a8ef31a1dc2ca
Signed-off-by: Jayant Shekhar <jshekhar@codeaurora.org>