usb: dwc3: qcom: Constify the software node

usb: dwc3: qcom: Constify the software node

What platform_device_add_properties() does is it allocates
dynamically a software node that will contain the device
properties supplied to it, and then couples that node with
the device. If the properties are constant, the node can be
constant as well.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20210204141711.53775-5-heikki.krogerus@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>