cros_setup_toolchains: check for root after processing flags

There's no need to require root just to process flags (like --help).

BUG=None
TEST=`./bin/cros_setup_toolchains --help` works as non-root
TEST=`./bin/cros_setup_toolchains` requires root

Change-Id: I324c27427476e2d14ec04d0443690ea30a8bf1fd
Reviewed-on: https://gerrit.chromium.org/gerrit/18655
Reviewed-by: Zdenek Behan <zbehan@chromium.org>
Commit-Ready: Mike Frysinger <vapier@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
diff --git a/scripts/cros_setup_toolchains.py b/scripts/cros_setup_toolchains.py
index 7b5bd76..fcbec81 100644
--- a/scripts/cros_setup_toolchains.py
+++ b/scripts/cros_setup_toolchains.py
@@ -19,10 +19,6 @@
 if not cros_build_lib.IsInsideChroot():
   print '%s: This needs to be run inside the chroot' % sys.argv[0]
   sys.exit(1)
-# This has to be always ran as root.
-if not os.getuid() == 0:
-  print "This script must be run as root!"
-  sys.exit(1)
 # Only import portage after we've checked that we're inside the chroot.
 # Outside may not have portage, in which case the above may not happen.
 import portage
@@ -598,5 +594,10 @@
 
   (options, _remaining_arguments) = parser.parse_args(argv)
 
+  # This has to be always ran as root.
+  if not os.getuid() == 0:
+    print "%s: This script must be run as root!" % sys.argv[0]
+    sys.exit(1)
+
   targets = set(options.targets.split(','))
   UpdateToolchains(options.usepkg, options.deleteold, options.hostonly, targets)