[analyzer] Fix unnecessary dyn_cast_or_null. No functionality change.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@152078 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/StaticAnalyzer/Checkers/MallocChecker.cpp b/lib/StaticAnalyzer/Checkers/MallocChecker.cpp
index 4309045..8a70476 100644
--- a/lib/StaticAnalyzer/Checkers/MallocChecker.cpp
+++ b/lib/StaticAnalyzer/Checkers/MallocChecker.cpp
@@ -1086,7 +1086,7 @@
   ASTContext &ASTC = State->getStateManager().getContext();
 
   // If it's one of the allocation functions we can reason about, we model
-  // it's behavior explicitly.
+  // its behavior explicitly.
   if (isa<FunctionDecl>(D) && isMemFunction(cast<FunctionDecl>(D), ASTC)) {
     return true;
   }
@@ -1097,7 +1097,7 @@
     return false;
 
   // Process C/ObjC functions.
-  if (const FunctionDecl *FD  = dyn_cast_or_null<FunctionDecl>(D)) {
+  if (const FunctionDecl *FD  = dyn_cast<FunctionDecl>(D)) {
     // White list the system functions whose arguments escape.
     const IdentifierInfo *II = FD->getIdentifier();
     if (!II)