CVE-2026-72119 can: bcm: extend bcm_tx_lock usage for data and timer updates

In the Linux kernel, the following vulnerability has been resolved: can: bcm: extend bcmtxlock usage for data and timer updates Stage new CAN frame content for an existing tx op into a kmalloc'd buffer and validate it there, mirroring the approach already used in bcmrxsetup. Only copy the validat...