Fix type validation for fmod and dmod

Since the dmod and fmod setter take a string as argument and convert them to a
base 8 integer, we don't need to check and convert in integer with the
configobj validator.

Signed-off-by: Sébastien Luttringer <sebastien.luttringer@smartjog.com>

installsystems/config.py

@@ -55,8 +55,8 @@ ionice_level = integer
 REPO_CONFIG_SPEC = """\
 [__many__]
     path = string
-    fmod = integer
-    dmod = integer
+    fmod = string
+    dmod = string
     uid = string
     gid = string
     offline = boolean