Set all of user's groups in "pmbootstrap install" (#1432)

The postmarketos-base package used to make the user part of the "video"
and "audio" groups. However, this did not work reliably, and we were
adding the "wheel" group in "pmbootstrap install" anyway.

Now all groups get added in "pmbootstrap install", and the names of the
groups have been moved to `pmb.config.install_user_groups`.

main/postmarketos-base/APKBUILD

@@ -1,6 +1,6 @@
 pkgname=postmarketos-base
 pkgver=3
-pkgrel=16
+pkgrel=17
 pkgdesc="Meta package for minimal postmarketOS base"
 url="https://github.com/postmarketOS"
 arch="noarch"

main/postmarketos-base/postmarketos-base.post-install

@@ -76,10 +76,6 @@ touch /etc/wpa_supplicant/wpa_supplicant.conf
 # Enable the 'wheel' group
 sed -i 's/# %wheel ALL=(ALL) ALL/%wheel ALL=(ALL) ALL/' /etc/sudoers
 
-# Add user to video group for proper framebuffer permissions
-username="$(getent passwd 1000 | cut -d ":" -f 1)"
-usermod -a -G video,audio "$username"
-
 # Set chrony to quickly correct system time on first boot, if necessary
 if ! grep -q "makestep" /etc/chrony/chrony.conf; then
 	echo "makestep 1 -1" >> /etc/chrony/chrony.conf