Add PKG_CHECK_MODULES sdbusplus to dependency list

Change-Id: Ia0c939ae6d116ee1c9feba770f56449ab1810db4
Signed-off-by: Matthew Barth <msbarth@us.ibm.com>
diff --git a/scripts/unit-test.py b/scripts/unit-test.py
index 652dfc2..f86e37d 100755
--- a/scripts/unit-test.py
+++ b/scripts/unit-test.py
@@ -143,7 +143,8 @@
             'log.hpp': 'phosphor-logging'
         },
         'PKG_CHECK_MODULES': {
-            'phosphor-dbus-interfaces': 'phosphor-dbus-interfaces'
+            'phosphor-dbus-interfaces': 'phosphor-dbus-interfaces',
+            'sdbusplus': 'sdbusplus'
         }
     }