ARM: dts: msm: Add linux,contiguous-region for 8x26 PIL regions

PIL is now being migrated from Ion to using CMA regions. Add
the phandle reference to the CMA regions for later use. This has
no effect until dma_alloc is called.

Change-Id: I4778ca04d3039a8408033a1ec36bb73f8436ee3a
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>