Fix Xorg detection condition.

packages/os.sh

@@ -87,6 +87,7 @@ done
 
 # graphics UI detection
 # basically just checks if an X server is running on the machine and if yes, we just assume it's a desktop, not a server
-if ps aux | grep Xorg >/dev/null 2>&1; then
+# grep will be always returned as a process with Xorg in the command line, so assume there must be a second process for this to succeed
+if [ $(ps aux | grep Xorg | wc -l) -gt 1 ]; then
 	add_tag "xorg_running" "desktop"
 fi