Remove \brief commands from doxygen comments.

This is similar to the LLVM change https://reviews.llvm.org/D46290.

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

Differential Revision: https://reviews.llvm.org/D46320

llvm-svn: 331834
diff --git a/clang/lib/Lex/Pragma.cpp b/clang/lib/Lex/Pragma.cpp
index db32e45..930c5f6 100644
--- a/clang/lib/Lex/Pragma.cpp
+++ b/clang/lib/Lex/Pragma.cpp
@@ -148,7 +148,7 @@
 
 namespace {
 
-/// \brief Helper class for \see Preprocessor::Handle_Pragma.
+/// Helper class for \see Preprocessor::Handle_Pragma.
 class LexingFor_PragmaRAII {
   Preprocessor &PP;
   bool InMacroArgPreExpansion;
@@ -588,7 +588,7 @@
   return LookUpIdentifierInfo(MacroTok);
 }
 
-/// \brief Handle \#pragma push_macro.
+/// Handle \#pragma push_macro.
 ///
 /// The syntax is:
 /// \code
@@ -611,7 +611,7 @@
   PragmaPushMacroInfo[IdentInfo].push_back(MI);
 }
 
-/// \brief Handle \#pragma pop_macro.
+/// Handle \#pragma pop_macro.
 ///
 /// The syntax is:
 /// \code
@@ -1730,7 +1730,7 @@
   }
 };
 
-/// \brief Handle "\#pragma region [...]"
+/// Handle "\#pragma region [...]"
 ///
 /// The syntax is
 /// \code