CVE-2026-99237: tracing: Hold trace_types_lock when resetting last boot data from readers

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

tracing: Hold tracetypeslock when resetting last boot data from readers

updatelastdataifempty() is called from tracingopen() with OTRUNC, tracingreadpipe() and tracingbuffersread() without tracetypeslock. Two readers can both pass the LASTBOOT test and free moduledelta twice, and a module notifier can update moduledelta while it is being freed.

Take tracetypeslock in those paths and keep the callers that already hold it on an unlocked variant.