ARM: dts: msm: Update mdsprpc apps CMA region in 8996

Add the entry for mdsprpc mem region that is used for sharing
memory of fastrpc buffers to MDSP processor.

Change-Id: I24724a772de122a07f85a8c36c1d5e421296a45c
Acked-by: Himateja Reddy <hmreddy@qti.qualcomm.com>
Signed-off-by: Sathish Ambley <sathishambley@codeaurora.org>