soc: qcom: pil: Remove null character writing of shared mem

PIL is writing '\0' in the shared mem region. This
region is shared with other clients that are also trying
to read. Hence they miss first character.

Remove this null character writing by PIL, as this mem
area is supposed to be Read only.

Change-Id: Ib7671256ca301afae4ab69bb1f8a87c529dc10cc
Signed-off-by: Jitendra Sharma <shajit@codeaurora.org>