ARM: dts: msm: Correct the register offset for modem PDC on SDM670

The offset in the PDC register for modem changed to 9 in SDM670
Changing the offset information in the DT.

Change-Id: I8a11e019db09ddf7f9e2fdefa696c94a9364ae22
Signed-off-by: Jitendra Sharma <shajit@codeaurora.org>