hw/xfree86: Support ACPI without APM.
On systems with ACPI but disabled APM (e.g. --disable-linux-apm) the code does not compile due to preprocessor directives.
If APM is disabled, the final return statement is considered to be part of ACPI's last if-statement, leading to a function which has no final return statement at all.
I have refactored the code so ACPI and APM are independent of each other.
Signed-off-by: Tobias Stoeckmann email@example.com