patch: DSE remove unused variable

[Jeffrey A Law]

On Tue, 2006-04-25 at 15:46 -0400, Aldy Hernandez wrote:
> Saw this while working on handling partial kills in DSE.
> 
> Bootstrapped on ppc-linux.  Regtests almost done.
> 
> OK?
> 
>         * tree-ssa-dse.c (dse_optimize_stmt): Remove unused variable USE.
OK once regression testing is complete.
jeff