Revert "ACPI / SBS: Add 5 us delay to fix SBS hangs on MacBook"

Revert commit 3349fb64 (ACPI / SBS: Add 5 us delay to fix SBS
hangs on MacBook), since the delay introduced by it is not necessary
any more after commit add68d6a (ACPI / SMBus: Fix boot stalls /
high CPU caused by reentrant code).

Signed-off-by: Chris Bainbridge <chris.bainbridge@gmail.com>
[ rjw: Changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>