CVE-2026-31726 usb: gadget: uvc: fix NULL pointer dereference during unbind race

In the Linux kernel, the following vulnerability has been resolved: usb: gadget: uvc: fix NULL pointer dereference during unbind race Commit b81ac4395bbe "usb: gadget: uvc: allow for application to cleanly shutdown" introduced two stages of synchronization waits totaling 1500ms in uvcfunctionunbi...