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/Analysis/Lint.cpp b/llvm/lib/Analysis/Lint.cpp
index 327f09a..db919bd 100644
--- a/llvm/lib/Analysis/Lint.cpp
+++ b/llvm/lib/Analysis/Lint.cpp
@@ -165,13 +165,13 @@
       }
     }
 
-    /// \brief A check failed, so printout out the condition and the message.
+    /// A check failed, so printout out the condition and the message.
     ///
     /// This provides a nice place to put a breakpoint if you want to see why
     /// something is not correct.
     void CheckFailed(const Twine &Message) { MessagesStr << Message << '\n'; }
 
-    /// \brief A check failed (with values to print).
+    /// A check failed (with values to print).
     ///
     /// This calls the Message-only version so that the above is easier to set
     /// a breakpoint on.