tdbtool: Use tdb_wipe_all in "erase" command

tdbtool: Use tdb_wipe_all in "erase" command

This is a lot quicker on large, fragmented databases. tdb_delete can
leave the freelist in a fragmented mess.

Also, it's a lot more robust: I've got a 4GB tdb file that was affected
by the problem fixed with c7211882a79. These databases have large space
at the end that is not part of any record or freelist
entry. tdb_wipe_all converts this space into a freelist entry. One
downside is that with those broken databases (which should not happen
after c7211882a79) have unallocated blocks in their file range after
this operation.

I think the speed advantage outweighs this disadvantage.

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>