Comment 1 for bug 1848750

The following patches were skipped since they've already been applied as cherry picks:

* efi/tpm: Don't access event->count when it isn't mapped
* efi/tpm: Don't traverse an event log with no events
* efi/tpm: Only set 'efi_tpm_final_log_size' after successful event log parsing
* blk-wbt: fix performance regression in wbt scale_up/scale_down