Build kernel tools along with other tools during world build, as well as

during kernel build (if they didn't get done with world).  This will make
-DMODULES_WITH_WORLD work, and it ensures the kernel tools are built
as part of 'make kernel-toolchain'.

Makefile.inc1

@@ -540,6 +540,7 @@ _cross-tools:
 	@echo ">>> stage 3: cross tools"
 	@echo "--------------------------------------------------------------"
 	${_+_}cd ${.CURDIR}; ${XMAKE} cross-tools
+	${_+_}cd ${.CURDIR}; ${XMAKE} kernel-tools
 _includes:
 	@echo
 	@echo "--------------------------------------------------------------"