Add support for qemuarm/64 machines with EFI

Fixes #667 (closed) Fixes docs#126 (closed)

TODO (do not merge if any pending):

• update docs
• mention new machines in build templates
• upstream edk2 and grub/grub-efi fixes - #766
• upstream the machines - #767 (closed)
• ci
• add ci jobs docs - #765
• drop unsupported machines from everywhere in this repo (qemuarm, qemuarm64, generic...)
• cleanup machine defconfigs - #770 (closed)

meta-oniro-core/conf/machine/qemuarm64-efi.conf

+# SPDX-FileCopyrightText: Huawei Inc.
+#
+# SPDX-License-Identifier: Apache-2.0
+
+#@TYPE: Machine
+#@NAME: qemuarm64-efi
+#@DESCRIPTION: Qemu Arm64 machine that boots via EFI.
+
+require conf/machine/include/arm/armv8a/tune-cortexa57.inc
+require conf/machine/include/qemu-efi.inc
+
+KERNEL_IMAGETYPE ?= "Image"
+
+# For runqemu
+QB_SYSTEM_NAME = "qemu-system-aarch64"
+QB_MACHINE_VIRT_HIGHMEM = "on"
+QB_CPU = "-cpu cortex-a57"