LDAP root DN creation fails

When keystone is configured to set up an LDAP server to use as
it's identity backend, the creation of the root DN fails.  The
problem is that one of the mods in the modify operation that sets
up the root DN is incorrect, which causes the entire modify
operation to fail.  The incorrect mod is attempting to configure
some attribute indexes, but one of the attributes it specifies is
undefined.  This patch removes the undefined attribute from the
template that is used to create the modify operation.

Change-Id: I413587130c64ca4f5f467b2ea1c0ab12867999ce
Closes-Bug: 1275158
Merge "LDAP root DN creation fails"