[libutils]  Modernize codebase by replacing NULL with nullptr

Fixes -Wzero-as-null-pointer-constant warning.

Test: m
Bug: 68236239
Change-Id: I5e89ec8c42151875439d2656475a8739ab9cb7dc
diff --git a/libutils/NativeHandle.cpp b/libutils/NativeHandle.cpp
index 97d06b8..d437a9f 100644
--- a/libutils/NativeHandle.cpp
+++ b/libutils/NativeHandle.cpp
@@ -20,7 +20,7 @@
 namespace android {
 
 sp<NativeHandle> NativeHandle::create(native_handle_t* handle, bool ownsHandle) {
-    return handle ? new NativeHandle(handle, ownsHandle) : NULL;
+    return handle ? new NativeHandle(handle, ownsHandle) : nullptr;
 }
 
 NativeHandle::NativeHandle(native_handle_t* handle, bool ownsHandle)