ARM: msm: Add board config support for 32 bit bengal apq iot

This change add board config support to enable build
32 bit kernel for bengal apq/qcs iot.

Change-Id: Ia3f0407f160a75c30b6ded4453e975b32ba8f637
Signed-off-by: Vijay Navnath Kamble <vkamble@codeaurora.org>