vmware: add GETTIME backdoor command (23) (#1590)
Returns the host's wall-clock time: EAX = seconds since the Unix epoch
(UTC), EBX = remaining microseconds, ECX = maximum time lag in
microseconds, EDX = host offset from UTC in minutes (east positive).
Guests only read the RTC at boot, so a VM resumed from a saved state
keeps running with the clock it was saved with. With this command a
small guest agent can periodically compare its clock against the host
and correct it without a reboot.