ARM: dts: msm: Add support to read FAB ID for PMICOBALT

REVID peripheral supports reading FAB ID value. Add property
qcom,fab-id-valid to allow clients to access the FAB ID data
for PMICOBALT.

Change-Id: I66463cf3fa7b0fdeba4cb5ee1e34d27b5e736cfb
Signed-off-by: Siddartha Mohanadoss <smohanad@codeaurora.org>