main/shutdown-clear-rtc-wakealarm: new aport

This contains an OpenRC service that clears the RTC wake alarm.
Users who don't want the RTC wake alarm to power on their phone from
powered-off state can use this service to clear the alarm during shutdown.

Fixes #1970

main/shutdown-clear-rtc-wakealarm/APKBUILD

+# Maintainer: Arnav Singh <me@arnavion.dev>
+pkgname=shutdown-clear-rtc-wakealarm
+pkgver=1.0.0
+pkgrel=0
+pkgdesc="Pre-shutdown service to clear RTC wake alarm"
+url="https://postmarketos.org"
+arch="noarch"
+license="MIT"
+source="
+	clear-rtc-wakealarm.shutdown.initd
+	"
+
+package() {
+	install -Dm755 "$srcdir"/clear-rtc-wakealarm.shutdown.initd "$pkgdir"/etc/init.d/clear-rtc-wakealarm
+}
+
+sha512sums="
+4223d3050113b6bfefa1c11394c059db7632e4a12793c476f467b8d1f4a3e9716074a46482eb705ca09e34cec251d4d65d3c3fe428404f17c72ccffb93f2e873  clear-rtc-wakealarm.shutdown.initd
+"

main/shutdown-clear-rtc-wakealarm/clear-rtc-wakealarm.shutdown.initd

+#!/sbin/openrc-run
+
+description="Clear RTC wake alarm during shutdown"
+
+# To use this service, add it to the shutdown runlevel with:
+#
+#     rc-update add clear-rtc-wakealarm shutdown
+
+start() {
+	echo 0 >/sys/class/rtc/rtc0/wakealarm
+}