Fix "errnor" typo in cros_sdk.

BUG=none
TEST=Try cros_sdk with missing version file.

Change-Id: I340c34b5202a9822092db81e21d2590f68318561
Reviewed-on: https://gerrit.chromium.org/gerrit/38950
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Commit-Ready: David James <davidjames@chromium.org>
Tested-by: David James <davidjames@chromium.org>
diff --git a/scripts/cros_sdk.py b/scripts/cros_sdk.py
index 0b916b7..efbf006 100644
--- a/scripts/cros_sdk.py
+++ b/scripts/cros_sdk.py
@@ -51,7 +51,7 @@
           raise Exception('Malformed version file; line %r' % raw_line)
         d[chunks[0]] = chunks[1].strip().strip('"')
   except EnvironmentError, e:
-    if e.errnor != errno.ENOENT:
+    if e.errno != errno.ENOENT:
       raise
   return d