Add support for using os-installer to install pmOS

This adds a new UI pkg for configuring/running os-installer, which is a nice little OS installer thing that we can use to install pmOS on laptops/tablets and stuff like that.

It runs under GNOME desktop, to support accessibility features and operate as a "live CD" like many other distro installer things do.

Under the hood, this is using pmbootstrap to install pmOS onto some local storage selected by the user in the os-installer UI. It defaults to targetting the device that the user is booted into. It will support FDE once a new pmbootstrap release is made with pmbootstrap!2538 (merged) in it.

Currently it only offers GNOME, KDE, and xfce desktop environments, but it's pretty easy to add more later.

main/postmarketos-ui-os-installer/APKBUILD

+# Reference: https://postmarketos.org/uipkg
+# Maintainer: Clayton Craft <clayton@craftyguy.net>
+pkgname=postmarketos-ui-os-installer
+pkgver=1
+pkgrel=0
+pkgdesc="UI for installing postmarketOS"
+url="https://gitlab.gnome.org/p3732/os-installer"
+# armhf blocked by gnome-shell -> gjs -> mozjs102
+arch="noarch !armhf"
+license="GPL-3.0-or-later"
+depends="
+	os-installer
+	pmbootstrap
+	postmarketos-ui-gnome
+	"
+source="
+	sysusers-os-installer.conf
+	gdm-custom.conf
+
+	config.yaml
+	distro.svg
+	pmos_setup.sh
+
+	gnome.jpg
+	kde.png
+	xfce.png
+"
+# NOTE: this UI *only* works with systemd
+options="!check pmb:systemd"
+replaces="gdm"
+
+_source440="
+	etc/doas.d/os-installer.conf
+"
+
+_source644="
+	etc/xdg/autostart/org.postmarketOS.os-installer.desktop
+	etc/gdm/custom.conf
+	usr/lib/sysusers.d/os-installer.conf
+	usr/lib/tmpfiles.d/os-installer.conf
+
+	etc/os-installer/config.yaml
+	etc/os-installer/distro.svg
+	etc/os-installer/desktops/gnome.jpg
+	etc/os-installer/desktops/kde.png
+	etc/os-installer/desktops/xfce.png
+"
+
+_source755="
+	usr/bin/pmos_setup.sh
+"
+
+flatpath() {
+	local i
+	for i in $@; do
+		echo "rootfs-$i" | sed s./.-.g
+	done
+}
+source="$(flatpath $_source440 $_source644 $_source755)"
+
+package() {
+	local i
+	for i in $_source440; do
+		install -Dm440 "$srcdir/$(flatpath "$i")" "$pkgdir/$i"
+	done
+	for i in $_source644; do
+		install -Dm644 "$srcdir/$(flatpath "$i")" "$pkgdir/$i"
+	done
+	for i in $_source755; do
+		install -Dm755 "$srcdir/$(flatpath "$i")" "$pkgdir/$i"
+	done
+
+	mkdir -p "$pkgdir"/etc/os-installer/scripts
+	ln -s /usr/bin/pmos_setup.sh \
+		"$pkgdir"/etc/os-installer/scripts/configure.sh
+	ln -s /usr/bin/pmos_setup.sh \
+		"$pkgdir"/etc/os-installer/scripts/install.sh
+	ln -s /usr/bin/pmos_setup.sh \
+		"$pkgdir"/etc/os-installer/scripts/prepare.sh
+}
+sha512sums="
+da5f5408cc58c9202989dfd5730499abe5977ef0ca7fd017dde657f1e1d84ebffb011a171778e0b74e28424ac39796aa97085ca8d9340446eb8e6def2b7e4c17  rootfs-etc-doas.d-os-installer.conf
+ebbff3d4c55d631e5c75c7de77852ea77cf0bae67349536ae7714616dbe2baf7762dd71578779670fc97d286ab8b26834e2b857bb843da421a5a4e81d96b3c37  rootfs-etc-xdg-autostart-org.postmarketOS.os-installer.desktop
+e51733f5c75649206ec99b96486fc33419541dd8ff6fe2ccd9eb8cba0920a004c6190362342ecd943c99f6d6e7c5e41e1992dbe4f3f42180dfab08fa06436911  rootfs-etc-gdm-custom.conf
+5d43fcfbbcda66497067eb665537b2e38e77f335ba58989e6a24af35f10e07cf1d10ba47cd7536de87bcf60fdb5c8582c7a84b7ffaa0c47c964b0b7ae6c95cae  rootfs-usr-lib-sysusers.d-os-installer.conf
+1d3268d5eed453a31bcdea1a9d6525a2a6f2172c7a54bdf0fbe6f01d6dbec4d4e793e5cabb03f97e80ae98a6a6712fc0391a2a1f0c19cf59f0bf698c06b10ac7  rootfs-usr-lib-tmpfiles.d-os-installer.conf
+863a4f36406e18094fee410b1f1f603a4df07a47331ad2a94c1ae6d28124e7cf1c88f800013603dfd3ac88e3d2e4fee263fe0cddd89cf7cd34e2d57b3455c574  rootfs-etc-os-installer-config.yaml
+98984fd67b99400d2b08422c4d314da558d3c94ee67dbc895e7bbfd6fdf22d4b2c9d35f48f4b73b383a054f535d4089fb705c5532f034cb2ee54eab2184e8e86  rootfs-etc-os-installer-distro.svg
+48736338cb0ead62b394812455742ef162dcc4000a4059408c21d8b3881891d54d57c01c21d65c40134b1b394b943cd53732e6b437aa60aa596599783f09f025  rootfs-etc-os-installer-desktops-gnome.jpg
+302261b7e63e259d70a77a9280a7e0abd909c0d389c7e5b873bfab96d87feb46768bc3feaf1a65e0820b9c25675d98ec34c990458f1c5aa0b273c9b754ade013  rootfs-etc-os-installer-desktops-kde.png
+41528fc57c6df41440923f11d6c43ff179d437c2591406a75b38f47165d3a11f278032c449044f08cb4d335bb37be4fc42ec3998a59af9ad061449c375ce0433  rootfs-etc-os-installer-desktops-xfce.png
+9299b7c55c1dd26447cadd9ab2deae635db56abee6731e1e195a7d376e0bcf97f829d3f355f713fd028a2ed7c0b267b8906bddba7b45771299dd58aac33a04ed  rootfs-usr-bin-pmos_setup.sh
+"