Remove \brief commands from doxygen comments.

We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.

Patch produced by

  for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done

Differential Revision: https://reviews.llvm.org/D46290

llvm-svn: 331272
diff --git a/llvm/unittests/Support/MD5Test.cpp b/llvm/unittests/Support/MD5Test.cpp
index 8b15182..bac1ec2 100644
--- a/llvm/unittests/Support/MD5Test.cpp
+++ b/llvm/unittests/Support/MD5Test.cpp
@@ -19,7 +19,7 @@
 using namespace llvm;
 
 namespace {
-/// \brief Tests an arbitrary set of bytes passed as \p Input.
+/// Tests an arbitrary set of bytes passed as \p Input.
 void TestMD5Sum(ArrayRef<uint8_t> Input, StringRef Final) {
   MD5 Hash;
   Hash.update(Input);