ptp: Fix possible memory leak in ptpclockregister()
This is an automated ID intended to aid in discovery of potential security vulnerabilities. The actual impact and attack plausibility have not yet been proven. This ID is fixed in Linux Kernel version v5.15 by commit 4225fea1cb28370086e17e82c0f69bec2779dca0, it was introduced in version v5.5 by commit a33121e5487b424339636b25c35d3a180eaa5f5e. For more details please see the references link.