ACPI: scheduling in atomic via acpi_evaluate_integer ()

Now I know why I had strange "scheduling in atomic" problems:
acpi_evaluate_integer() does malloc(..., irqs_disabled() ? GFP_ATOMIC
: GFP_KERNEL)... which is (of course) broken.

There's no way to reliably tell if we need GFP_ATOMIC or not from
code, this one for example fails to detect spinlocks held.

Fortunately, allocation seems small enough to be done on stack.

Signed-off-by: Pavel Machek <pavel@suse.cz>
Acked-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>