Update credibility.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27589 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/CREDITS.TXT b/CREDITS.TXT
index 9067388..ecba30a 100644
--- a/CREDITS.TXT
+++ b/CREDITS.TXT
@@ -89,6 +89,7 @@
 N: Jim Laskey
 E: jlaskey@apple.com
 D: Improvements to the PPC backend, instruction scheduling
+D: Debug implementation, Dwarf implementation
 
 N: Chris Lattner
 E: sabre@nondot.org