Makefile: toolchain-eclipse-register: add toolchain dependency

The "toolchain-eclipse-register" target needs the toolchain so add
toolchain as a dependency.
This also fix the support to top-level parallel make.

Signed-off-by: Fabio Porcedda <fabio.porcedda@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

Makefile

@@ -621,7 +621,7 @@ target-post-image: $(TARGETS_ROOTFS) target-finalize
 		$(call MESSAGE,"Executing post-image script $(s)"); \
 		$(EXTRA_ENV) $(s) $(BINARIES_DIR) $(call qstrip,$(BR2_ROOTFS_POST_SCRIPT_ARGS))$(sep))
 
-toolchain-eclipse-register:
+toolchain-eclipse-register: toolchain
 	./support/scripts/eclipse-register-toolchain `readlink -f $(O)` $(notdir $(TARGET_CROSS)) $(BR2_ARCH)
 
 source: $(TARGETS_SOURCE) $(HOST_SOURCE)