Remove ChangeLog entry unintentionally duplicated in the top level

From-SVN: r229695

ChangeLog

-2015-11-02  Alexandre Oliva <aoliva@redhat.com>
-
-	PR tree-optimization/68083
-	* tree-ssa-ifcombine.c: Include tree-ssa.h.
-	(bb_no_side_effects_p): Test for undefined uses too.
-	* tree-ssa.c (gimple_uses_undefined_value_p): New.
-	* tree-ssa.h (gimple_uses_undefined_value_p): Declare.
-
 2015-10-23  Steve Ellcey  <sellcey@imgtec.com>
 
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