NO_ROOT: Create the METALOG directory on installworld/distributeworld.

When not using NO_ROOT the DESTDIR is implicitly created by the
distrib-dirs call.  However with NO_ROOT it is trying to write
to the METALOG right away before running distrib-dirs which
may fail.

Sponsored by:	EMC / Isilon Storage Division

Makefile.inc1

@@ -959,6 +959,7 @@ distributeworld installworld: _installcheck_world
 	cp $$libs $$progs ${INSTALLTMP}
 	cp -R $${PATH_LOCALE:-"/usr/share/locale"} ${INSTALLTMP}/locale
 .if defined(NO_ROOT)
+	-mkdir -p ${METALOG:H}
 	echo "#${MTREE_MAGIC}" > ${METALOG}
 .endif
 .if make(distributeworld)