armvirt: add EFI support

EFI booting is used on newer machines compatible with the
Arm SystemReady specifications.

This commit restructures armvirt into a more 'generic'
target similar to x86.

See https://github.com/openwrt/openwrt/pull/4956
for a history of this port.

Signed-off-by: Mathew McBride <matt@traverse.com.au>

target/linux/armvirt/base-files/lib/preinit/01_sysinfo_acpi

@@ -0,0 +1,52 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+
+sanitize_name_arm64() {
+	sed -e '
+		y/ABCDEFGHIJKLMNOPQRSTUVWXYZ/abcdefghijklmnopqrstuvwxyz/;
+		s/[^a-z0-9_-]\+/-/g;
+		s/^-//;
+		s/-$//;
+	' "$@"
+}
+
+do_sysinfo_arm64() {
+	local vendor product file
+
+	for file in sys_vendor board_vendor; do
+		vendor="$(cat /sys/devices/virtual/dmi/id/$file 2>/dev/null)"
+		case "$vendor" in
+		empty | \
+		System\ manufacturer | \
+		To\ [bB]e\ [fF]illed\ [bB]y\ O\.E\.M\.)
+			continue
+			;;
+		esac
+		[ -n "$vendor" ] && break
+	done
+
+	for file in product_name board_name; do
+		product="$(cat /sys/devices/virtual/dmi/id/$file 2>/dev/null)"
+		case "$vendor:$product" in
+		?*:empty | \
+		?*:System\ Product\ Name | \
+		?*:To\ [bB]e\ [fF]illed\ [bB]y\ O\.E\.M\.)
+			continue
+			;;
+		?*:?*)
+			break
+			;;
+		esac
+	done
+
+	[ -d "/sys/firmware/devicetree/base" ] && return
+
+	[ -n "$vendor" -a -n "$product" ] || return
+
+	mkdir -p /tmp/sysinfo
+
+	echo "$vendor $product" > /tmp/sysinfo/model
+
+	sanitize_name_arm64 /tmp/sysinfo/model > /tmp/sysinfo/board_name
+}
+
+boot_hook_add preinit_main do_sysinfo_arm64