[rfc]: Use trad_frame_alloc_saved_regs in alpha-tdep

[Joel Brobecker]

> This patch makes alpha-tdep use trad_frame_alloc_saved_regs. I'd appreciate 
> it very much if someone with access to an alpha machine could run the 
> testsuite.

I used to be able to test on alpha-tru64, but for some reason the
testsuite no longer runs on our machines. It looks more like a tcl/expect
problem than anything else. I don't know if there are any other people
out there would can test on an alpha machine...

Sorry :-(.

-- 
Joel