MFC UEFI memstick build script

r264935 (gjb):

    Add a separate script to build the memstick.img and the
    mini-memstick.img with UEFI support.

    As the comments in the file suggest, 1) there must
    be existing ${.OBJDIR}/usr/src/release/{release,bootonly};
    2) TARGET/TARGET_ARCH must be amd64; and 3) it must be
    a vt(4)-enabled kernel with vt_efifb (*not* vt_vga).

    This script is not hooked into release/Makefile in any way
    until further testing is complete.

r264992 (nwhitehorn):

    Make a dual-boot BIOS/UEFI memstick image. Testing required before
    this gets renamed make-memstick.sh.

r265017 (nwhitehorn):

    loader's GPT support on BIOS does not seem to like the root
    filesystem being the last filesystem on the disk for some reason
    when made by this script. Add a vestigial swap partition to allow
    this to boot with QEMU BIOS.

Approved by:	re
Sponsored by:	The FreeBSD Foundation

release/amd64/make-uefi-memstick.sh

@@ -0,0 +1,41 @@
+#!/bin/sh
+#
+# This script generates a "memstick image" (image that can be copied to a
+# USB memory stick) from a directory tree.  Note that the script does not
+# clean up after itself very well for error conditions on purpose so the
+# problem can be diagnosed (full filesystem most likely but ...).
+#
+# Usage: make-memstick.sh <directory tree> <image filename>
+#
+# $FreeBSD$
+#
+
+PATH=/bin:/usr/bin:/sbin:/usr/sbin
+export PATH
+
+if [ $# -ne 2 ]; then
+	echo "make-memstick.sh /path/to/directory /path/to/image/file"
+	exit 1
+fi
+
+if [ ! -d ${1} ]; then
+	echo "${1} must be a directory"
+	exit 1
+fi
+
+if [ -e ${2} ]; then
+	echo "won't overwrite ${2}"
+	exit 1
+fi
+
+echo '/dev/ufs/FreeBSD_Install / ufs ro,noatime 1 1' > ${1}/etc/fstab
+makefs -B little -o label=FreeBSD_Install ${2}.part ${1}
+if [ $? -ne 0 ]; then
+	echo "makefs failed"
+	exit 1
+fi
+rm ${1}/etc/fstab
+
+mkimg -s gpt -b ${1}/boot/pmbr -p efi:=${1}/boot/boot1.efifat -p freebsd-boot:=${1}/boot/gptboot -p freebsd-ufs:=${2}.part -p freebsd-swap::1M -o ${2}
+rm ${2}.part
+