usb: cdnsp: add support for eUSB2v2 port

usb: cdnsp: add support for eUSB2v2 port

The Cadence CDNSP controller optionally supports eUSB2 (embedded USB2)
port. While this port type operates logically like high-speed USB 2.0,
it utilizes a different physical layer signaling.

This patch:
- Extends the port detection logic to recognize the eUSB2 protocol.
- Tracks the eUSB2 port offset in the cdnsp_device structure.
- Ensures that eUSB2 ports are correctly handled during Link State
  transitions, specifically forcing L0 when LPM is capable, similar
  to standard USB 2.0 ports.

Signed-off-by: Pawel Laszczak <pawell@cadence.com>
Acked-by: Peter Chen <peter.chen@kernel.org>
Link: https://patch.msgid.link/20260420-eusb2v2_upstream-v2-1-9883645e2ede@cadence.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>