ARM: dts: msm: Fix i2c i2c-src-freq in fsm9900

Set i2c-src-freq to 19.2M for reliable operation.

Change-Id: Ia0e403387e7640b00b6857efe248c8c32cf64638
Acked-by: Kaushik Sikdar <ksikdar@qti.qualcomm.com>
Signed-off-by: Venkatesh Yadav Abbarapu <quicvenkat@codeaurora.org>