The architecture is currently unmaintained, remove.

Cc: Benjamin Matthews <mben12@gmail.com>
Cc: Chong Huang <chuang@ucrobotics.com>
Cc: Dimitar Penev <dpn@switchfin.org>
Cc: Haitao Zhang <hzhang@ucrobotics.com>
Cc: I-SYST Micromodule <support@i-syst.com>
Cc: M.Hasewinkel (MHA) <info@ssv-embedded.de>
Cc: Marek Vasut <marex@denx.de>
Cc: Martin Strubel <strubel@section5.ch>
Cc: Peter Meerwald <devel@bct-electronic.com>
Cc: Sonic Zhang <sonic.adi@gmail.com>
Cc: Valentin Yakovenkov <yakovenkov@niistt.ru>
Cc: Wojtek Skulski <info@skutek.com>
Cc: Wojtek Skulski <skulski@pas.rochester.edu>
Signed-off-by: Tom Rini <trini@konsulko.com>

Introduce a Makefile under arch/$ARCH/ and include it in the
top Makefile (similar to Linux kernel). This allows further
refactoringi like moving architecture-specific code out of global
makefiles, deprecating config variables (CPU, CPUDIR, SOC) or
deprecating arch/$ARCH/config.mk.

In contrary to Linux kernel, U-Boot defines the ARCH variable by
Kconfig, thus the arch Makefile can only included conditionally
after the top config.mk.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Acked-by: Masahiro Yamada <yamada.m@jp.panasonic.com>