ARM: dts: qcom: Change SMEM base address for 8939

With new memory map for 8939, the base address of SMEM has been
changed. Modify the DT file to address this change.

CRs-Fixed: 658539
Change-Id: I01e5d119041b045bb988b946434282d1827cd313
Signed-off-by: Zaheerulla Meer <zmeer@codeaurora.org>