Fix Buster packages

stage3/00-install-packages/00-packages-nr

@@ -1,6 +1,6 @@
 xserver-xorg-video-fbdev xserver-xorg xinit xserver-xorg-video-fbturbo
 epiphany-browser
-lxde lxtask menu-xdg gksu
-netsurf-gtk zenity xdg-utils
+lxde lxtask menu-xdg
+zenity xdg-utils
 gvfs-backends gvfs-fuse
 lightdm gnome-themes-standard-data gnome-icon-theme

stage4/00-install-packages/00-packages

@@ -10,7 +10,7 @@ python3-numpy
 pypy
 alacarte rc-gui sense-hat
 tree
-libgl1-mesa-dri libgles1-mesa libgles2-mesa xcompmgr
+libgl1-mesa-dri libgles1 libgles2-mesa xcompmgr
 geany
 piclone
 wiringpi pigpio python-pigpio python3-pigpio raspi-gpio python-gpiozero python3-gpiozero python3-rpi.gpio
@@ -22,5 +22,5 @@ python-picraft python3-picraft
 pprompt
 piwiz
 rp-prefapps
-libav-tools
+ffmpeg
 vlc