This fixes keyboard event handling on some systems.

Note that this delay was thought unnecessary, and removed
from linux-2.6.20 with 50c1e113
'ACPI: ec: Drop udelay() from poll mode. Loop by reading status field instead.'
Signed-off-by: NAlexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: NLen Brown <len.brown@intel.com>