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/MAINTAINERS b/MAINTAINERS
index 5069f18..4ed72ae 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -108,6 +108,15 @@
 F:	doc/device-tree-bindings/mmc/snps,dw-mmc.txt
 F:	drivers/mmc/snps_dw_mmc.c
 
+APPLE M1 SOC SUPPORT
+M:	Mark Kettenis <kettenis@openbsd.org>
+S:	Maintained
+F:	arch/arm/include/asm/arch-m1/
+F:	arch/arm/mach-apple/
+F:	configs/apple_m1_defconfig
+F:	drivers/iommu/apple_dart.c
+F:	include/configs/apple.h
+
 ARM
 M:	Tom Rini <trini@konsulko.com>
 S:	Maintained