obmc-phosphor-systemd.bbclass: Update configparser module class name

There is a warning message in the obmc-phosphor-systemd.bbclass file
when using bitbake to build image-bmc:
```
DeprecationWarning: The SafeConfigParser class has been renamed to
ConfigParser in Python 3.2. This alias will be removed in future
versions. Use ConfigParser directly instead.
  parser = configparser.SafeConfigParser(strict=False)
```
Use the class name `ConfigParser` directly in the configparser module.

Signed-off-by: George Liu <liuxiwei@inspur.com>
Change-Id: I6168d9d1100ac846cc31be837a20b7dedb6d7910
diff --git a/meta-phosphor/classes/obmc-phosphor-systemd.bbclass b/meta-phosphor/classes/obmc-phosphor-systemd.bbclass
index c67fc02..b1398e0 100644
--- a/meta-phosphor/classes/obmc-phosphor-systemd.bbclass
+++ b/meta-phosphor/classes/obmc-phosphor-systemd.bbclass
@@ -99,7 +99,7 @@
 
 def systemd_parse_unit(d, path):
     import configparser
-    parser = configparser.SafeConfigParser(strict=False)
+    parser = configparser.ConfigParser(strict=False)
     parser.optionxform = str
     parser.read('%s' % path)
     return parser