ARM: dts: msm: Add memshare for msm8996

Memshare driver allocates and share the memory with the clients
sitting on modem so that they can use it. Add device tree
information for memshare driver for msm8996.

CRs-Fixed: 970173
Change-Id: Ib93a9d60fc4a22f0755cecb6ff3ea8e2457d2d28
Signed-off-by: Manoj Prabhu B <bmanoj@codeaurora.org>