Wrong return type for syncrepl_del_nonpresent()

[Hallvard B Furuseth <h.b.furuseth@usit.uio.no>]

I won't dignify this with an ITS, but:  Either
slapd/syncrepl.c:syncrepl_del_nonpresent() should have return type void,
or it should return some value which its callers should test.

-- 
Hallvard