ARM: exynos: move sysram info to exynos.c

This solves a problem with building with CONFIG_SMP=n due to missing
sysram_base_addr (or sysram_ns_base_addr) variables.

The new setup method is more awkward than I'd like for it to be, but
it can't be done in init_early() since ioremap is not yet available,
but it needs to happen before SMP.

Reported-by: Russell King <linux@arm.linux.org.uk>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Olof Johansson <olof@lixom.net>
Reviewed-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>