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/lib/Target/AArch64/AArch64TargetTransformInfo.cpp b/llvm/lib/Target/AArch64/AArch64TargetTransformInfo.cpp
index 337db54..316ea04 100644
--- a/llvm/lib/Target/AArch64/AArch64TargetTransformInfo.cpp
+++ b/llvm/lib/Target/AArch64/AArch64TargetTransformInfo.cpp
@@ -38,7 +38,7 @@
   return (CallerBits & CalleeBits) == CalleeBits;
 }
 
-/// \brief Calculate the cost of materializing a 64-bit value. This helper
+/// Calculate the cost of materializing a 64-bit value. This helper
 /// method might only calculate a fraction of a larger immediate. Therefore it
 /// is valid to return a cost of ZERO.
 int AArch64TTIImpl::getIntImmCost(int64_t Val) {
@@ -54,7 +54,7 @@
   return (64 - LZ + 15) / 16;
 }
 
-/// \brief Calculate the cost of materializing the given constant.
+/// Calculate the cost of materializing the given constant.
 int AArch64TTIImpl::getIntImmCost(const APInt &Imm, Type *Ty) {
   assert(Ty->isIntegerTy());