gooftool: Fix get_firmware_hash exception

BUG=chromium:834300
TEST=manually test on DUT

Change-Id: I55ce184ff670321387bd6a6a72d00bdb208c4c60
Reviewed-on: https://chromium-review.googlesource.com/1017020
Commit-Ready: Cheng-Han Yang <chenghan@chromium.org>
Tested-by: Cheng-Han Yang <chenghan@chromium.org>
Reviewed-by: Yong Hong <yhong@google.com>
diff --git a/py/gooftool/commands.py b/py/gooftool/commands.py
index fbeb4a2..3d571c1 100755
--- a/py/gooftool/commands.py
+++ b/py/gooftool/commands.py
@@ -761,11 +761,9 @@
 def GetFirmwareHash(options):
   """Get firmware hash from a file"""
   if os.path.exists(options.file):
-    hashes = chromeos_firmware.CalculateFirmwareHashes(options.file)
-    for section, value_dict in hashes.iteritems():
-      print '%s:' % section
-      for key, value in value_dict.iteritems():
-        print '  %s: %s' % (key, value)
+    value_dict = chromeos_firmware.CalculateFirmwareHashes(options.file)
+    for key, value in value_dict.iteritems():
+      print '  %s: %s' % (key, value)
   else:
     raise Error('File does not exist: %s' % options.file)