Fix typo: objc_no_direct_instance_variable_assignmemt => objc_no_direct_instance_variable_assignment.

Fixes <rdar://problem/12927551>.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@170971 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/StaticAnalyzer/Checkers/Checkers.td b/lib/StaticAnalyzer/Checkers/Checkers.td
index 10881b3..ef9e17d 100644
--- a/lib/StaticAnalyzer/Checkers/Checkers.td
+++ b/lib/StaticAnalyzer/Checkers/Checkers.td
@@ -421,7 +421,7 @@
   DescFile<"DirectIvarAssignment.cpp">;
 
 def DirectIvarAssignmentForAnnotatedFunctions : Checker<"DirectIvarAssignmentForAnnotatedFunctions">,
-  HelpText<"Check for direct assignments to instance variables in the methods annotated with objc_no_direct_instance_variable_assignmemt">,
+  HelpText<"Check for direct assignments to instance variables in the methods annotated with objc_no_direct_instance_variable_assignment">,
   DescFile<"DirectIvarAssignment.cpp">;
 
 def ObjCSuperCallChecker : Checker<"MissingSuperCall">,