usb: dwc3: Add dwc pointer to dwc3_readl/writel

usb: dwc3: Add dwc pointer to dwc3_readl/writel

Use dwc pointer in dwc3_readl() dwc3_writel() instead of passing
the dwc->regs. This would help us access the dwc structure and
log the base address in traces. There's no functional changes in
this patch, just refactoring existing APIs.

Signed-off-by: Prashanth K <prashanth.k@oss.qualcomm.com>
Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://patch.msgid.link/20260114100748.2950103-3-prashanth.k@oss.qualcomm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>