Libbase: NOLINT legacy unique_fd operator int

The use in implicit conversion is intentional.

Test: m
Change-Id: I6c756e772b274e8a525ba2ad792cc4a8e1fc0176
diff --git a/base/include/android-base/unique_fd.h b/base/include/android-base/unique_fd.h
index 4e6c879..c8d12cf 100644
--- a/base/include/android-base/unique_fd.h
+++ b/base/include/android-base/unique_fd.h
@@ -103,7 +103,7 @@
   void reset(int new_value = -1) { reset(new_value, nullptr); }
 
   int get() const { return fd_; }
-  operator int() const { return get(); }
+  operator int() const { return get(); }  // NOLINT
 
   int release() __attribute__((warn_unused_result)) {
     tag(fd_, this, nullptr);