ARM: dts: msm: specify MEM ACC L2 custom data for msm8939

MSM8939 target needs L2 custom data to be configured into
custom mem acc register. Pass the necessary register address
and the configuration data through device node.

CRs-Fixed: 715818
Change-Id: I5034a6fe8a47cef60b8c27ec50b65c1bcac12734
Signed-off-by: Tirupathi Reddy <tirupath@codeaurora.org>