ARM: dts: msm: add FG GEN3 device on pmicobalt

FG GEN3 peripheral is present on pmicobalt and it provides the
battery parameters like current, voltage, resistance and
temperature for the clients that depend on them. Add FG GEN3
device on pmicobalt to support that.

Change-Id: I7ebb6a50564abc8e607f688d59690c55c10e2dc9
Signed-off-by: Subbaraman Narayanamurthy <subbaram@codeaurora.org>