[C++11] Replace some comparisons with 'nullptr' with simple boolean checks to reduce verbosity.

llvm-svn: 205829
diff --git a/llvm/lib/Support/ManagedStatic.cpp b/llvm/lib/Support/ManagedStatic.cpp
index e358fe8..c05cd22 100644
--- a/llvm/lib/Support/ManagedStatic.cpp
+++ b/llvm/lib/Support/ManagedStatic.cpp
@@ -24,7 +24,7 @@
   if (llvm_is_multithreaded()) {
     llvm_acquire_global_lock();
 
-    if (Ptr == nullptr) {
+    if (!Ptr) {
       void* tmp = Creator ? Creator() : nullptr;
 
       TsanHappensBefore(this);