ARM: 7020/1: Check for multiple zreladdrs

Without CONFIG_AUTO_ZRELADDR being set the kernel needs a single
zreladdr for building zImages. Bail out if we detect multiple
zreladdrs without CONFIG_AUTO_ZRELADDR.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>