build: make node-gyp output silent

As it is, node-gyp produces a lot of build related verbose messages.
Latest node-gyp upgrade allows us to specify --silent flag to suppress
those messages. Except for CI, addons build will run silently.

PR-URL: #8990

Reviewed-By: Daniel Bevenius <daniel.bevenius@gmail.com>
Reviewed-By: Gibson Fahnestock <gibfahn@gmail.com>
Reviewed-By: Ilkka Myller <ilkka.myller@nodefield.com>
Reviewed-By: Fedor Indutny <fedor.indutny@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Rod Vagg <rod@vagg.org>

Makefile

@@ -8,6 +8,7 @@ PREFIX ?= /usr/local
 FLAKY_TESTS ?= run
 TEST_CI_ARGS ?=
 STAGINGSERVER ?= node-www
+LOGLEVEL ?= silent
 OSTYPE := $(shell uname -s | tr '[A-Z]' '[a-z]')
 
 ifdef JOBS
@@ -163,7 +164,8 @@ test/addons/.buildstamp: config.gypi \
  # Cannot use $(wildcard test/addons/*/) here, it's evaluated before
  # embedded addons have been generated from the documentation.
  for dirname in test/addons/*/; do \
- $(NODE) deps/npm/node_modules/node-gyp/bin/node-gyp rebuild \
+ echo "\nRunning addons test $$PWD/$$dirname" ; \
+ $(NODE) deps/npm/node_modules/node-gyp/bin/node-gyp --loglevel=$(LOGLEVEL) rebuild \
  --python="$(PYTHON)" \
  --directory="$$PWD/$$dirname" \
  --nodedir="$$PWD" || exit 1 ; \
@@ -193,6 +195,7 @@ CI_NATIVE_SUITES := addons
 CI_JS_SUITES := doctool inspector known_issues message parallel pseudo-tty sequential
 
 # Build and test addons without building anything else
+test-ci-native: LOGLEVEL := info
 test-ci-native: | test/addons/.buildstamp
  $(PYTHON) tools/test.py $(PARALLEL_ARGS) -p tap --logfile test.tap \
  --mode=release --flaky-tests=$(FLAKY_TESTS) \
@@ -204,6 +207,7 @@ test-ci-js:
  --mode=release --flaky-tests=$(FLAKY_TESTS) \
  $(TEST_CI_ARGS) $(CI_JS_SUITES)
 
+test-ci: LOGLEVEL := info
 test-ci: | build-addons
  out/Release/cctest --gtest_output=tap:cctest.tap
  $(PYTHON) tools/test.py $(PARALLEL_ARGS) -p tap --logfile test.tap \