Improve messaging and binary generation for pkcs11

Signed-off-by: Riyaz Faizullabhoy <riyaz.faizullabhoy@docker.com>

Dockerfile.gccgo

@@ -71,7 +71,7 @@ RUN useradd --create-home --gid docker unprivilegeduser
 
 VOLUME /var/lib/docker
 WORKDIR /go/src/github.com/docker/docker
-ENV DOCKER_BUILDTAGS apparmor pkcs11 seccomp selinux
+ENV DOCKER_BUILDTAGS apparmor seccomp selinux
 
 # Wrap all commands in the "docker-in-docker" script to allow nested containers
 ENTRYPOINT ["hack/dind"]

hack/make/.build-deb/rules

@@ -6,7 +6,7 @@ override_dh_gencontrol:
 	# if we're on Ubuntu, we need to Recommends: apparmor
 	echo 'apparmor:Recommends=$(shell dpkg-vendor --is Ubuntu && echo apparmor)' >> debian/docker-engine.substvars
 	# recommend yubico-piv-tool since we include pkcs11 by default
-	echo 'yubico:Recommends=$(echo "yubico-piv-tool (>= 1.1.0~)")' >> debian/docker-engine.substvars
+	echo 'yubico:Recommends="yubico-piv-tool (>= 1.1.0~)"' >> debian/docker-engine.substvars
 	dh_gencontrol
 
 override_dh_auto_build:

hack/make/.build-rpm/docker-engine.spec

@@ -60,7 +60,7 @@ Requires: device-mapper >= 1.02.90-2
 %global with_selinux 1
 %endif
 
-# yubico-piv-tool required
+# yubico-piv-tool recommends
 %if 0%{?fedora} >= 20 || 0%{?centos} >= 7 || 0%{?rhel} >= 7
 Requires: yubico-piv-tool >= 1.1.0
 %endif