bindings: Skip the default ifaces on enumerate

The C++ mapper will now return D-Bus object paths that only
contain the 3 default D-Bus interfaces:
* org.freedesktop.DBus.Introspectable
* org.freedesktop.DBus.Peer
* org.freedesktop.DBus.Properties

Whereas before it would filter out these paths.

As these paths aren't explicitly hosted by a service,
trying to do a GetAll method to read their properties,
which would occur during an enumerate REST operation,
would fail.

The fix is to skip trying to read properties on these
interfaces.

Change-Id: I9b306a4fbefa78c60f739c1351cd32ee2c36c234
Signed-off-by: Matt Spinler <spinler@us.ibm.com>
diff --git a/obmc/mapper/bindings.py b/obmc/mapper/bindings.py
index 8fbcd51..8024105 100644
--- a/obmc/mapper/bindings.py
+++ b/obmc/mapper/bindings.py
@@ -24,6 +24,12 @@
 MAPPER_PATH = '/xyz/openbmc_project/object_mapper'
 MAPPER_NOT_FOUND = 'org.freedesktop.DBus.Error.FileNotFound'
 
+# The default D-Bus interfaces that we don't need to get
+# properties on during an enumerate.
+DEFAULT_IFACES = ['org.freedesktop.DBus.Introspectable',
+                  'org.freedesktop.DBus.Peer',
+                  'org.freedesktop.DBus.Properties']
+
 
 class Mapper:
     def __init__(self, bus):
@@ -108,6 +114,8 @@
         for i in interfaces:
             if match and not match(i):
                 continue
+            if i in DEFAULT_IFACES:
+                continue
             properties.update(self.__get_properties_on_iface(
                 properties_iface, i))