Please clean build output [cosmetic]

[traumschule]

On debian buster 32-bit with node 9.11.2 and npm 5.6.0 we get following output:

> segfault-handler@1.0.1 install /home/user/src/node-segfault-handler
> node-gyp rebuild

make: Entering directory '/home/user/src/node-segfault-handler/build'
  CXX(target) Release/obj.target/segfault-handler/src/segfault-handler.o
In file included from /home/user/.node-gyp/9.11.2/include/node/node.h:63,
                 from ../node_modules/nan/nan.h:52,
                 from ../src/segfault-handler.cpp:2:
/home/user/.node-gyp/9.11.2/include/node/v8.h: In static member function ‘static void v8::V8::RemoveGCPrologueCallback(v8::GCCallback)’:
/home/user/.node-gyp/9.11.2/include/node/v8.h:10378:53: warning: cast between incompatible function types from ‘v8::GCCallback’ {aka ‘void (*)(v8::GCType, v8::GCCallbackFlags)’} to ‘v8::Isolate::GCCallback’ {aka ‘void (*)(v8::Isolate*, v8::GCType, v8::GCCallbackFlags)’} [-Wcast-function-type]
       reinterpret_cast<Isolate::GCCallback>(callback));
                                                     ^
/home/user/.node-gyp/9.11.2/include/node/v8.h: In static member function ‘static void v8::V8::RemoveGCEpilogueCallback(v8::GCCallback)’:
/home/user/.node-gyp/9.11.2/include/node/v8.h:10385:53: warning: cast between incompatible function types from ‘v8::GCCallback’ {aka ‘void (*)(v8::GCType, v8::GCCallbackFlags)’} to ‘v8::Isolate::GCCallback’ {aka ‘void (*)(v8::Isolate*, v8::GCType, v8::GCCallbackFlags)’} [-Wcast-function-type]
       reinterpret_cast<Isolate::GCCallback>(callback));
                                                     ^
In file included from ../src/segfault-handler.cpp:2:
../node_modules/nan/nan.h: In function ‘void Nan::AsyncQueueWorker(Nan::AsyncWorker*)’:
../node_modules/nan/nan.h:2208:62: warning: cast between incompatible function types from ‘void (*)(uv_work_t*)’ {aka ‘void (*)(uv_work_s*)’} to ‘uv_after_work_cb’ {aka ‘void (*)(uv_work_s*, int)’} [-Wcast-function-type]
     , reinterpret_cast<uv_after_work_cb>(AsyncExecuteComplete)
                                                              ^
In file included from ../node_modules/nan/nan.h:52,
                 from ../src/segfault-handler.cpp:2:
../src/segfault-handler.cpp: At global scope:
/home/user/.node-gyp/9.11.2/include/node/node.h:505:43: warning: cast between incompatible function types from ‘void (*)(Nan::ADDON_REGISTER_FUNCTION_ARGS_TYPE)’ {aka ‘void (*)(v8::Local<v8::Object>)’} to ‘node::addon_register_func’ {aka ‘void (*)(v8::Local<v8::Object>, v8::Local<v8::Value>, void*)’} [-Wcast-function-type]
       (node::addon_register_func) (regfunc),                          \
                                           ^
/home/user/.node-gyp/9.11.2/include/node/node.h:539:3: note: in expansion of macro ‘NODE_MODULE_X’
   NODE_MODULE_X(modname, regfunc, NULL, 0)  // NOLINT (readability/null_usage)
   ^~~~~~~~~~~~~
../src/segfault-handler.cpp:339:3: note: in expansion of macro ‘NODE_MODULE’
   NODE_MODULE(segfault_handler, init)
   ^~~~~~~~~~~
In file included from /home/user/.node-gyp/9.11.2/include/node/node.h:63,
                 from ../node_modules/nan/nan.h:52,
                 from ../src/segfault-handler.cpp:2:
/home/user/.node-gyp/9.11.2/include/node/v8.h: In instantiation of ‘void v8::PersistentBase<T>::SetWeak(P*, typename v8::WeakCallbackInfo<P>::Callback, v8::WeakCallbackType) [with P = node::ObjectWrap; T = v8::Object; typename v8::WeakCallbackInfo<P>::Callback = void (*)(const v8::WeakCallbackInfo<node::ObjectWrap>&)]’:
/home/user/.node-gyp/9.11.2/include/node/node_object_wrap.h:85:78:   required from here
/home/user/.node-gyp/9.11.2/include/node/v8.h:9338:16: warning: cast between incompatible function types from ‘v8::WeakCallbackInfo<node::ObjectWrap>::Callback’ {aka ‘void (*)(const v8::WeakCallbackInfo<node::ObjectWrap>&)’} to ‘Callback’ {aka ‘void (*)(const v8::WeakCallbackInfo<void>&)’} [-Wcast-function-type]
                reinterpret_cast<Callback>(callback), type);
                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/user/.node-gyp/9.11.2/include/node/v8.h: In instantiation of ‘void v8::PersistentBase<T>::SetWeak(P*, typename v8::WeakCallbackInfo<P>::Callback, v8::WeakCallbackType) [with P = Nan::ObjectWrap; T = v8::Object; typename v8::WeakCallbackInfo<P>::Callback = void (*)(const v8::WeakCallbackInfo<Nan::ObjectWrap>&)]’:
../node_modules/nan/nan_object_wrap.h:66:61:   required from here
/home/user/.node-gyp/9.11.2/include/node/v8.h:9338:16: warning: cast between incompatible function types from ‘v8::WeakCallbackInfo<Nan::ObjectWrap>::Callback’ {aka ‘void (*)(const v8::WeakCallbackInfo<Nan::ObjectWrap>&)’} to ‘Callback’ {aka ‘void (*)(const v8::WeakCallbackInfo<void>&)’} [-Wcast-function-type]
  SOLINK_MODULE(target) Release/obj.target/segfault-handler.node
  COPY Release/segfault-handler.node
make: Leaving directory '/home/user/src/node-segfault-handler/build'
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This may not be serious but clutters the build log of our project.