[wtp-releng] Build Failed notices only to this list from now on

[David M Williams <david_williams@xxxxxxxxxx>]

In the past, build-failed notices went
to wtp-dev, as well as wtp-releng. 

Turns out these are not useful, since
there's a lot of spurious failures, and the 
sent link to the build problem does
not work well. 

So .... subscribe to this list :) 

Note: it might take a litle while to
"take effect", but will either be in a few hours, 
or the next time CC is re-started.