arm: apple: Add initial support for Apple's M1 SoC

Add support for Apple's M1 SoC that is used in "Apple Silicon"
Macs.  This builds a basic U-Boot that can be used as a payload
for the m1n1 boot loader being developed by the Asahi Linux
project.

Signed-off-by: Mark Kettenis <kettenis@openbsd.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
[trini: Add MAINTAINERS entry]
diff --git a/arch/arm/mach-apple/Makefile b/arch/arm/mach-apple/Makefile
new file mode 100644
index 0000000..e74a8c9
--- /dev/null
+++ b/arch/arm/mach-apple/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0+
+
+obj-y += board.o
+obj-y += lowlevel_init.o