binman: Don't show image-skip message by default

This message is not very important since it is simply indicating that the
user's instructions are being followed. Only show it when the verbosity
level is above the default.

Also drop the unnecessary extra newline on this message, which causes two
line breaks.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/tools/binman/ftest.py b/tools/binman/ftest.py
index e77fce5..75658c9 100644
--- a/tools/binman/ftest.py
+++ b/tools/binman/ftest.py
@@ -187,7 +187,8 @@
         return control.Binman(options, args)
 
     def _DoTestFile(self, fname, debug=False, map=False, update_dtb=False,
-                    entry_args=None, images=None, use_real_dtb=False):
+                    entry_args=None, images=None, use_real_dtb=False,
+                    verbosity=None):
         """Run binman with a given test file
 
         Args:
@@ -210,6 +211,8 @@
             args.append('-up')
         if not use_real_dtb:
             args.append('--fake-dtb')
+        if verbosity is not None:
+            args.append('-v%d' % verbosity)
         if entry_args:
             for arg, value in entry_args.iteritems():
                 args.append('-a%s=%s' % (arg, value))
@@ -1459,13 +1462,22 @@
 
     def testSelectImage(self):
         """Test that we can select which images to build"""
-        with test_util.capture_sys_output() as (stdout, stderr):
-            retcode = self._DoTestFile('006_dual_image.dts', images=['image2'])
-        self.assertEqual(0, retcode)
-        self.assertIn('Skipping images: image1', stdout.getvalue())
+        expected = 'Skipping images: image1'
 
-        self.assertFalse(os.path.exists(tools.GetOutputFilename('image1.bin')))
-        self.assertTrue(os.path.exists(tools.GetOutputFilename('image2.bin')))
+        # We should only get the expected message in verbose mode
+        for verbosity in (None, 2):
+            with test_util.capture_sys_output() as (stdout, stderr):
+                retcode = self._DoTestFile('006_dual_image.dts',
+                                           verbosity=verbosity,
+                                           images=['image2'])
+            self.assertEqual(0, retcode)
+            if verbosity:
+                self.assertIn(expected, stdout.getvalue())
+            else:
+                self.assertNotIn(expected, stdout.getvalue())
+
+            self.assertFalse(os.path.exists(tools.GetOutputFilename('image1.bin')))
+            self.assertTrue(os.path.exists(tools.GetOutputFilename('image2.bin')))
 
     def testUpdateFdtAll(self):
         """Test that all device trees are updated with offset/size info"""