litex_setup: revert default install behaviour but add --user support

litex_setup.py

@@ -26,7 +26,7 @@ repos = OrderedDict(repos)
 if len(sys.argv) < 2:
     print("Available commands:")
     print("- init")
-    print("- install")
+    print("- install (add --user to install to user directory)")
     print("- update")
     exit()
 
@@ -46,7 +46,10 @@ if "install" in sys.argv[1:]:
         print("[installing " + name + "]...")
         if need_develop:
             os.chdir(os.path.join(current_path, name))
+            if "--user" in sys.argv[1:]:
                 os.system("python3 setup.py develop --user")
+            else:
+                os.system("python3 setup.py develop")
 
 if "update" in sys.argv[1:]:
     for name in repos.keys():