Fix various problems pointed out by Andrew Morton and others:
* platform_device_unregister checks for NULL, no need to check here.
* Formatting fixes.
* Remove big macro and convert to a function.
* Use strcmp instead of defining a broken case-insensitive comparison,
and make the output parameter info match the case of the input one
(change "I/O" to "i/o").
* Return the length instead of 0 from the hotmod parameter handler.
* Remove some unused cruft.
* The trydefaults parameter only has to do with scanning the "standard"
addresses, don't check for that on ACPI.