LDB:test-generic.sh - fix smaller/greater comparison tests

LDB:test-generic.sh - fix smaller/greater comparison tests

The comparison result has been ignored, which is not good. Also remove
the "ldbsearch" command in the error branch which has not much sense.

The scripts needs to be run through test-tdb.sh, test-ldap.sh or
test-sqlite3.sh which I didn't realise before. Hence less changes are needed
and this is a reduced version of the patch published on the mailing list.

Signed-off-by: Matthias Dieter Wallnöfer <mdw@samba.org>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>