binman: Expand the error message for breaching a section

Add in a few more details to this error message to make it easier to see
what is going on.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/binman/ftest.py b/tools/binman/ftest.py
index adc1603..4f7e226 100644
--- a/tools/binman/ftest.py
+++ b/tools/binman/ftest.py
@@ -970,8 +970,9 @@
         """Test that the end-at-4gb property checks for offset boundaries"""
         with self.assertRaises(ValueError) as e:
             self._DoTestFile('028_pack_4gb_outside.dts')
-        self.assertIn("Node '/binman/u-boot': Offset 0x0 (0) is outside "
-                      "the section starting at 0xffffffe0 (4294967264)",
+        self.assertIn("Node '/binman/u-boot': Offset 0x0 (0) size 0x4 (4) "
+                      "is outside the section '/binman' starting at "
+                      '0xffffffe0 (4294967264) of size 0x20 (32)',
                       str(e.exception))
 
     def testPackX86Rom(self):