CVE-2026-43319 spi: spidev: fix lock inversion between spi_lock and buf_lock

In the Linux kernel, the following vulnerability has been resolved: spi: spidev: fix lock inversion between spilock and buflock The spidev driver previously used two mutexes, spilock and buflock, but acquired them in different orders depending on the code path: write/read: buflock - spilock ioctl...