Use externally defined npm if provided

Ce sont les modifications que j'ai dû effectuer pour cross-compiler. J'avais oublié de le sauver.

Merci.

release/Makefile

@@ -6,7 +6,7 @@
 # Requires the following dependencies:
 #  * Python 2.7 (build only)
 #  * NodeJS >=10.x (build and runtime)
-#  * npm (build only)
+#  * $(NPM) (build only)
 #  * Rust (build only)
 #
 # Following parameters may be provided:
@@ -94,7 +94,7 @@ index.html: $(call nodedep,duniter-ui) $(addprefix node_modules/,$(leveldown.COM
 
 node_modules/%.node: $(call nodedep,nw-gyp) $(call nodedep,nw)
 	@$(if $($(call simplename,$@).PREPARE),$($(call simplename,$@).PREPARE))
-	@PATH=$(shell npm bin):${PATH} node-pre-gyp \
+	@PATH=$(shell $(NPM) bin):${PATH} node-pre-gyp \
 		-C node_modules/$(call simplename,$@) \
 		--runtime=node-webkit \
 		--target=$(NW_VERSION) \
@@ -105,17 +105,17 @@ node_modules/%.node: $(call nodedep,nw-gyp) $(call nodedep,nw)
 	@cp "node_modules/$(call simplename,$@)/$($(call simplename,$@).INTERMEDIATE)/$(notdir $@)" "$@"
 
 node_modules/%/package.json: | node_modules
-	@NEON_BUILD_RELEASE="true" npm add $*$($*.VERSION)
+	@NEON_BUILD_RELEASE="true" $(NPM) add $*$($*.VERSION)
 
 node_modules:
-	@npm uninstall husky
-	@NEON_BUILD_RELEASE="true" npm install
+	@$(NPM) uninstall husky
+	@NEON_BUILD_RELEASE="true" $(NPM) install
 
 # Wipe the delivery result
 .PHONY: wipe
 wipe:
-	@npm uninstall nw-gyp
-	@PATH=$(shell npm bin):${PATH} npm prune --production
+	@$(NPM) uninstall nw-gyp
+	@PATH=$(shell $(NPM) bin):${PATH} $(NPM) prune --production
 	@find -name "*.ts" ! -name "*.d.ts" -delete
 ifneq ($(ADD_DEBUG),Y)
 	@find -name "*.d.ts" -delete -o -name "*.js.map" -delete