build: add target specific build_type variable

This commit add a target specific variable named 'build_type' to the
node and node_g targets.

The motivation for doing this is that both targets share the same
prerequisites, and the recepies are the same (apart from the build type)
so some duplication can be avoided.

PR-URL: #33925
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: James M Snell <jasnell@gmail.com>

Makefile

@@ -98,13 +98,12 @@ help: ## Print help for targets with comments.
 # and recreated which can break the addons build when running test-ci
 # See comments on the build-addons target for some more info
 ifeq ($(BUILD_WITH), make)
-$(NODE_EXE): config.gypi out/Makefile
-	$(MAKE) -C out BUILDTYPE=Release V=$(V)
-	if [ ! -r $@ -o ! -L $@ ]; then ln -fs out/Release/$(NODE_EXE) $@; fi
-
-$(NODE_G_EXE): config.gypi out/Makefile
-	$(MAKE) -C out BUILDTYPE=Debug V=$(V)
-	if [ ! -r $@ -o ! -L $@ ]; then ln -fs out/Debug/$(NODE_EXE) $@; fi
+$(NODE_EXE): build_type:=Release
+$(NODE_G_EXE): build_type:=Debug
+$(NODE_EXE) $(NODE_G_EXE): config.gypi out/Makefile
+	$(MAKE) -C out BUILDTYPE=${build_type} V=$(V)
+	if [ ! -r $@ -o ! -L $@ ]; then \
+	  ln -fs out/${build_type}/$(NODE_EXE) $@; fi
 else
 ifeq ($(BUILD_WITH), ninja)
 ifeq ($(V),1)