platform: msm: qcom-geni-se: Add support for 32-bit kernel

Add macro for DMA address mask, as the existing code doesn't
support 32-bit architecture.

Change-Id: Iaddb9e11f7ba094f22c84e2b700239f5f7e107c3
Signed-off-by: Shrey Vijay <shreyv@codeaurora.org>