[inputflinger] Modernize codebase by replacing NULL with nullptr

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

Test: m
Bug: 68236239
Change-Id: I0d06ab2a187e72bd893900355edad97caa684c7a
diff --git a/services/inputflinger/InputApplication.cpp b/services/inputflinger/InputApplication.cpp
index 9e90631..c56dfe6 100644
--- a/services/inputflinger/InputApplication.cpp
+++ b/services/inputflinger/InputApplication.cpp
@@ -25,7 +25,7 @@
 // --- InputApplicationHandle ---
 
 InputApplicationHandle::InputApplicationHandle() :
-    mInfo(NULL) {
+    mInfo(nullptr) {
 }
 
 InputApplicationHandle::~InputApplicationHandle() {
@@ -35,7 +35,7 @@
 void InputApplicationHandle::releaseInfo() {
     if (mInfo) {
         delete mInfo;
-        mInfo = NULL;
+        mInfo = nullptr;
     }
 }