The time sync related interrupt registers may be manipulated from
different contexts. This patch protects the registers from being
asynchronously changed by the reset function.

Also, the patch removes a misleading comment. The reset function
is disabling a bunch of functions, not enabling them.
Signed-off-by: Richard Cochran <richardcochran@gmail.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>