ACPI: clean up white space in a few places for consistency

This cleans up a few line spaces so that it is consistent with the rest
of the file. There are a few places where a space was added before a
return and two spots where a double line space was made into one line
space.

Signed-off-by: Ian Cowan <ian@linux.cowan.aero>
[ rjw: Subject adjustment ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>