This patch robustifies gdb.thread/linux-dp.exp.  gdbserver cannot report thread 
creation events, rather than mark such non-appearances as unresolved, this marks 
them as unsupported.  It also checks the thread table before and after thread 
creation to make sure the expected threads show up there.

ok?

nathan
-- 
Nathan Sidwell    ::   http://www.codesourcery.com   ::         CodeSourcery
nathan@codesourcery.com    ::     http://www.planetfall.pwp.blueyonder.co.uk