selftest: rtc: Add to check rtc alarm status for alarm related test

selftest: rtc: Add to check rtc alarm status for alarm related test

In alarm_wkalm_set and alarm_wkalm_set_minute test, they use different
ioctl (RTC_ALM_SET/RTC_WKALM_SET) for alarm feature detection. They will
skip testing if RTC_ALM_SET/RTC_WKALM_SET ioctl returns an EINVAL error
code. This design may miss detecting real problems when the
efi.set_wakeup_time() return errors and then RTC_ALM_SET/RTC_WKALM_SET
ioctl returns an EINVAL error code with RTC_FEATURE_ALARM enabled.

In order to make rtctest more explicit and robust, we propose to use
RTC_PARAM_GET ioctl interface to check rtc alarm feature state before
running alarm related tests. If the kernel does not support RTC_PARAM_GET
ioctl interface, we will fallback to check the error number of
(RTC_ALM_SET/RTC_WKALM_SET) ioctl call for alarm feature detection.

Requires commit 101ca8d05913b ("rtc: efi: Enable SET/GET WAKEUP services
as optional")

Reviewed-by: Koba Ko <kobak@nvidia.com>
Reviewed-by: Matthew R. Ochs <mochs@nvidia.com>
Signed-off-by: Joseph Jang <jjang@nvidia.com>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>