atrtc.c: handle _STA object indcate it is not functional.

[takawata]

Summary

Enable cmos register access from ACPI only and relux register access restriction when RTC _STA object indicate not functional. This is needed for upcoming ACPI000E device (I name it acpi_rtc.) for some implementation.

[wulf]

sys/x86/isa/atrtc.c

508

blank line is missed

510

- if (acpi_rtc_is_present){
+ if (acpi_rtc_is_present) {

514

- }else{
+ } else {

534

blank line is missed

535

- if(sc->is_active)
+ if (sc->is_active)

[wulf]

sys/x86/isa/atrtc.c

298

I do not understand what !acpi_rtc_is_present check does here.
This code opens a lot of RTC registers for write if execution of _STA method returned 'Not present'.
To make region handler dummy, if it is required, !acpi_rtc_is_present check should be moved to atrtc_acpi_cmos_handler() and should return AE_OK on success.
P.S. soft context is available in atrtc_acpi_cmos_handler(), so acpi_rtc_is_present global variable may be converted to sc->is_present