usb: xhci: optimize resuming from S4 (suspend-to-disk)

usb: xhci: optimize resuming from S4 (suspend-to-disk)

On resume from S4 (power loss after suspend/hibernation), the xHCI
driver previously freed, reallocated, and fully reinitialized all
data structures. Most of this is unnecessary because the data is
restored from a saved image; only the xHCI registers lose their values.

This patch optimizes S4 resume by performing only a host controller
reset, which includes:
* Freeing or clearing runtime-created data.
* Rewriting xHCI registers.

Signed-off-by: Niklas Neronin <niklas.neronin@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://patch.msgid.link/20260402131342.2628648-13-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>