Rename DEBUG macro to LLVM_DEBUG.
    
The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM
- Manual change to APInt
- Manually chage DOCS as regex doesn't match it.

In the transition period the DEBUG() macro is still present and aliased
to the LLVM_DEBUG() one.

Differential Revision: https://reviews.llvm.org/D43624

llvm-svn: 332240
diff --git a/llvm/lib/Target/Mips/MipsSEISelLowering.cpp b/llvm/lib/Target/Mips/MipsSEISelLowering.cpp
index 12916c0..a62ae07 100644
--- a/llvm/lib/Target/Mips/MipsSEISelLowering.cpp
+++ b/llvm/lib/Target/Mips/MipsSEISelLowering.cpp
@@ -1040,11 +1040,9 @@
   }
 
   if (Val.getNode()) {
-    DEBUG(dbgs() << "\nMipsSE DAG Combine:\n";
-          N->printrWithDepth(dbgs(), &DAG);
-          dbgs() << "\n=> \n";
-          Val.getNode()->printrWithDepth(dbgs(), &DAG);
-          dbgs() << "\n");
+    LLVM_DEBUG(dbgs() << "\nMipsSE DAG Combine:\n";
+               N->printrWithDepth(dbgs(), &DAG); dbgs() << "\n=> \n";
+               Val.getNode()->printrWithDepth(dbgs(), &DAG); dbgs() << "\n");
     return Val;
   }