perf/x86/intel: Fix large period handling on Broadwell CPUs

I'd like to nominate commit f605cfca8c39 ("perf/x86/intel: Fix large period handling on Broadwell CPUs") for backport to the affected stable Linux releases. (The bug was introduced in 4.1.)

Because of this bug, the NMI watchdog timer may fire spuriously on Broadwell systems, resulting in a hard lockup panic when there is, in fact, no lockup.