CVE-2026-74603: ptp: ocp: Fix board ID over-read

In the Linux kernel, the following vulnerability has been resolved:

ptp: ocp: Fix board ID over-read

The EEPROM board ID is a fixed 13-byte field and is not guaranteed to contain a NUL terminator. Passing it directly to devlinkinfoversionfixedput() treats it as a C string and may read beyond the field.

Format at most OCPBOARDIDLEN bytes into the existing local buffer before reporting the ID. Use a precision limit because the snprintf() output size alone does not bound the source string scan.