package/nodejs: fix parallel build further

Commit 84c24ab1b5a7 (package/nodejs: fix parallel build) made use of
BR2_JLEVEL to set the number of jobs nodejs should use instead of using
the number of CPUs (+2).

However, BR2_JLEVEL can be set to 0 by the user, to let Buildroot detect
the number of CPUs (+1), and stores it in PARALLEL_JOBS, and leaves
BR2_JLEVEL untouched, so 0.

Thus, we can end up spawning a build by passing -j0 to ninja, which it
interprets as "no -limit yolo" and does not limit the number oj jobs it
spawns, which usually ends up in an OOM somewhere...

Fix this by using PARALLEL_JOBS.

Reported-by: Cédric & Co
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
(cherry picked from commit d574e2a4f440903a0e32de6deb8275b1f385da2e)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/nodejs/nodejs.mk

@@ -47,7 +47,7 @@ HOST_NODEJS_MAKE_OPTS = \
 	LDFLAGS.host="$(HOST_LDFLAGS)" \
 	NO_LOAD=cctest.target.mk \
 	PATH=$(@D)/bin:$(BR_PATH) \
-	JOBS=$(BR2_JLEVEL)
+	JOBS=$(PARALLEL_JOBS)
 
 NODEJS_MAKE_OPTS = \
 	$(TARGET_CONFIGURE_OPTS) \
@@ -55,7 +55,7 @@ NODEJS_MAKE_OPTS = \
 	PATH=$(@D)/bin:$(BR_PATH) \
 	LDFLAGS="$(NODEJS_LDFLAGS)" \
 	LD="$(TARGET_CXX)" \
-	JOBS=$(BR2_JLEVEL)
+	JOBS=$(PARALLEL_JOBS)
 
 # nodejs's build system uses python which can be a symlink to an unsupported
 # python version (e.g. python 3.10 with nodejs 14.18.1). We work around this by