ARM: dts: msm: Remove extcon for USB2.0 on QCS405

On QCS405, all the platforms does not have SMB
charger present, so remove the extcon property for
USB2.0 on the default dt file for QCS405.

Change-Id: I4df0e55939da1add1ef13b28921d10acfd88ec7c
Signed-off-by: Sriharsha Allenki <sallenki@codeaurora.org>