Don't record self-link from mw.title

Every Lua-using page loads the "self" title for mw.title. But we don't
want to record this self-link in the links table, because that confuses
people.

Change-Id: I1ef57daa615c176b7789f5f09bd15ee5b292ad0c
Merge "Don't record self-link from mw.title"