usb: dwc3: core: move the core check before soft reset

We read the DWC3_GSNPSID register to make sure we got the correct
register offset passed. One of the recent commits moved the soft reset
before this so in case of the wrong offset we end up with "reset timed
out". This patch moves the "id" check before the reset again.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>