With multiboard support the compiletime generated BOARDINFO string
gets more and more meaningless. This removes it from Kconfig and
replaces it with a variable that can be set at boardlevel.

Also many boards have a standard setting for the hostname in the
environment. This patch also moves the standard to C code by calling
barebox_set_hostname().

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

This architecture is a bit strange. It has up to four SDRAM banks, but
all have a quite limited size. The SDRAM size for the different boards
currently is unknown as it's configurable with Kconfig. We use a SDRAM
size based on the value of the only board we have in the defconfigs:
edb9301. This likely breaks other ep93xx boards.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Add support for the Cirrus Logic EP93xx platform

Signed-off-by: Matthias Kaehlcke <matthias@kaehlcke.net>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>