ifupdown2: fix a few regex parsing error messages

Ticket:
Reviewed By: CCR-3804
Testing Done: Tested regex parsing failures

This is mostly a cosmetic fix. we were failing with weird/unclear errors
on unable to parse regex expressions correctly.
This patch mainly adds the interface name to the message and plus adds
an info message showing the actual regex being used in searches.

example config:
{noformat}
auto br-roopa
iface br-roopa
  bridge-vlan-aware yes
  bridge-ports regex '(\\Aswp3\\Z|\\Aswp4\\Z)'
  bridge-pvid 20
{noformat}

before the patch:
warning: br-roopa: error getting dependent interfaces (unbalanced
parenthesis)

after the patch (not pretty but easier to debug)

info: br-roopa: evaluating port expr '['regex', "'(", 'Aswp3', 'Z|',
'Aswp4', "Z)'"]'
warning: br-roopa: error getting dependent interfaces (br-roopa: error
searching regex ''(' in swp38 (unbalanced parenthesis))

(cherry picked from commit bcca6f753a25494666d53f1f2f3c855ffa41d7f0)

addons/bond.py

@@ -122,7 +122,8 @@ class bond(moduleBase):
 
         if not self._is_bond(ifaceobj):
             return None
-        slave_list = self.parse_port_list(ifaceobj.get_attr_value_first(
+        slave_list = self.parse_port_list(ifaceobj.name,
+                                    ifaceobj.get_attr_value_first(
                                     'bond-slaves'), ifacenames_all)
         ifaceobj.dependency_type = ifaceDependencyType.MASTER_SLAVE
         # Also save a copy for future use
@@ -146,7 +147,7 @@ class bond(moduleBase):
             return ifaceobj.priv_data
         slaves = ifaceobj.get_attr_value_first('bond-slaves')
         if slaves:
-            return self.parse_port_list(slaves)
+            return self.parse_port_list(ifaceobj.name, slaves)
         else:
             return None
 
@@ -273,7 +274,7 @@ class bond(moduleBase):
         attrval = ifaceobj.get_attrs_value_first(['bond-lacp-bypass-priority',
                                 'bond-lacp-fallback-priority'])
         if attrval:
-            portlist = self.parse_port_list(attrval)
+            portlist = self.parse_port_list(ifaceobj.name, attrval)
             if not portlist:
                 self.log_warn('%s: could not parse \'%s %s\''
                               %(ifaceobj.name, attrname, attrval))