arm/dt: pm8941/pm8226: drop chg prefix for qcom,chg devices

Drop the unecessary chg prefix for SMBB and SMBBP charger
peripherals.

Note that the qcom,chg-misc peripheral will not drop this
prefix to avoid confusion with the MISC device which
already uses qcom,misc as a device name.

Change-Id: I9b85ab87449a2fe5f4bfa6fd2c51268c9b81f2cb
Signed-off-by: David Keitel <dkeitel@codeaurora.org>