Don't build packages that haven't been selected.

Currently, when configure --with-config is used, selective compilation
is only effective for the simple "make" case. Package builders (e.g.
make rpm) still build everything (utils and modules). This patch fixes
that.

Signed-off-by: Prakash Surya <surya1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #851

config/deb.am

@@ -15,6 +15,7 @@ deb-local:
 	fi)
 
 deb-modules: deb-local rpm-modules
+if CONFIG_KERNEL
 	name=${PACKAGE}-modules; \
 	version=${ZFS_META_VERSION}-${ZFS_META_RELEASE}; \
 	release=`echo ${LINUX_VERSION} | $(SED) -e "s/-/_/g"`; \
@@ -23,8 +24,10 @@ deb-modules: deb-local rpm-modules
 	pkg2=$${name}-devel-$${version}_$${release}.$${arch}.rpm; \
 	fakeroot $(ALIEN) --scripts --to-deb $$pkg1 $$pkg2; \
 	$(RM) $$pkg1 $$pkg2
+endif
 
 deb-utils: deb-local rpm-utils
+if CONFIG_USER
 	name=${PACKAGE}; \
 	version=${ZFS_META_VERSION}-${ZFS_META_RELEASE}; \
 	arch=`$(RPM) -qp $${name}-$${version}.src.rpm --qf %{arch} | tail -1`; \
@@ -34,5 +37,6 @@ deb-utils: deb-local rpm-utils
 	pkg4=$${name}-dracut-$${version}.$${arch}.rpm; \
 	fakeroot $(ALIEN) --scripts --to-deb $$pkg1 $$pkg2 $$pkg3 $$pkg4; \
 	$(RM) $$pkg1 $$pkg2 $$pkg3 $$pkg4
+endif
 
 deb: deb-modules deb-utils