release: Add an image for CI

A lot of projects CI can't do FreeBSD tests currently.
The main reason is that the project CI infrastructure is runned on Linux
and that our images aren't modifiable from a Linux hosts.
Add a basic image specific for this case (called BASIC-CI for a lack of a
better name).
The image have no package pre-installed.
It only have a few modification to have dhcp client runned on the default
interface and sshd started with option to be able to log on without a password
as root.

Sponsored by: The FreeBSD Foundation

Reviewed by:	re (gjb@)
Differential Revision:	https://reviews.freebsd.org/D25598

release/Makefile.vm

@@ -16,13 +16,17 @@ VMDK_DESC=	VMWare, VirtualBox disk image
 QCOW2_DESC=	Qemu, KVM disk image
 RAW_DESC=	Unformatted raw disk image
 
-CLOUDWARE?=	EC2 \
+CLOUDWARE?=	BASIC-CI \
+		EC2 \
 		GCE \
 		VAGRANT-VIRTUALBOX \
 		VAGRANT-VMWARE
 AZURE_FORMAT=	vhdf
 AZURE_DESC=	Microsoft Azure platform image
 AZURE_DISK=	${OSRELEASE}.${AZURE_FORMAT}
+BASIC-CI_FORMAT=	raw
+BASIC-CI_DESC=		Image for CI
+BASIC-CI_DISK=	${OSRELEASE}.${BASIC-CI_FORMAT}
 EC2_FORMAT=	raw
 EC2_DESC=	Amazon EC2 image
 EC2_DISK=	${OSRELEASE}.${EC2_FORMAT}

release/tools/basic-ci.conf

@@ -0,0 +1,35 @@
+#!/bin/sh
+#
+# $FreeBSD$
+#
+
+# Should be enough for base image, image can be resized in needed
+export VMSIZE=5G
+
+# Set to a list of third-party software to enable in rc.conf(5).
+export VM_RC_LIST="sshd growfs"
+
+vm_extra_pre_umount() {
+	cat << EOF >> ${DESTDIR}/etc/rc.conf
+dumpdev="AUTO"
+ifconfig_DEFAULT="DHCP"
+sshd_enable="YES"
+EOF
+
+	cat << EOF >> ${DESTDIR}/boot/loader.conf
+autoboot_delay="-1"
+beastie_disable="YES"
+loader_logo="none"
+console="comconsole,vidconsole"
+EOF
+    cat <<EOF >> ${DESTDIR}/etc/ssh/sshd_config
+PermitRootLogin yes
+PasswordAuthentication yes
+PermitEmptyPasswords yes
+UsePAM no
+EOF
+
+	touch ${DESTDIR}/firstboot
+
+	return 0
+}