fedup --clean should exit parse_args() early

`fedup --clean` is basically a different mode than normal fedup, so we
need to skip the rest of the argument parsing if we're doing cleanup.

Resolves: rhbz#1158766

fedup/commandline.py

@@ -128,6 +128,10 @@ def parse_args(gui=False):
 
     args = p.parse_args()
 
+    if args.clean:
+        args.resetbootloader = True
+        return args
+
     if not (gui or args.network or args.device or args.iso or args.clean):
         p.error(_('SOURCE is required (--network, --device, --iso)'))
 
@@ -139,10 +143,6 @@ def parse_args(gui=False):
     if args.instrepo and args.instrepokey:
         args.repos.append(('gpgkey', 'instrepo=%s' % args.instrepokey))
 
-    if not gui:
-        if args.clean:
-            args.resetbootloader = True
-
     # Fedora.next: upgrades to F21 require --product
     if legacy_fedora:
         if args.product is None: