[binder] Replace NULL/0 with nullptr

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

clang-tidy -checks=modernize-use-nullptr -p compile_commands.json -fix
...

Test: m
Bug: 68236239
Change-Id: I3181bc5683796423a98b0f9b94daf30880c07bdc
diff --git a/libs/binder/tests/binderThroughputTest.cpp b/libs/binder/tests/binderThroughputTest.cpp
index bf41e0b..b790997 100644
--- a/libs/binder/tests/binderThroughputTest.cpp
+++ b/libs/binder/tests/binderThroughputTest.cpp
@@ -380,7 +380,7 @@
             // Caller specified the max latency in microseconds.
             // No need to run training round in this case.
             if (atoi(argv[i+1]) > 0) {
-                max_time_bucket = strtoull(argv[i+1], (char **)NULL, 10) * 1000;
+                max_time_bucket = strtoull(argv[i+1], (char **)nullptr, 10) * 1000;
                 time_per_bucket = max_time_bucket / num_buckets;
                 i++;
             } else {