ACPI: ibm-acpi: kill trailing whitespace

I shall protect the ibm-acpi city against the invasion of the barbarian
blanks!  To the unforgiving jaws of sed s/[[:blank:]]\+$// they go!

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Len Brown <len.brown@intel.com>