ARM: 7022/1: allow to detect conflicting zreladdrs

Boards used to specify zreladdr in their Makefile.boot with
zreladdr-y := x, so conflicting zreladdrs were silently overwritten.
This patch changes this to zreladdr-y += x, so that we end
up with multiple words in zreladdr in such a case. We can
detect this later and complain if necessary.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mach-ep93xx/Makefile.boot b/arch/arm/mach-ep93xx/Makefile.boot
index 0ad33f1..d3113a7 100644
--- a/arch/arm/mach-ep93xx/Makefile.boot
+++ b/arch/arm/mach-ep93xx/Makefile.boot
@@ -1,14 +1,14 @@
-   zreladdr-$(CONFIG_EP93XX_SDCE3_SYNC_PHYS_OFFSET)	:= 0x00008000
+   zreladdr-$(CONFIG_EP93XX_SDCE3_SYNC_PHYS_OFFSET)	+= 0x00008000
 params_phys-$(CONFIG_EP93XX_SDCE3_SYNC_PHYS_OFFSET)	:= 0x00000100
 
-   zreladdr-$(CONFIG_EP93XX_SDCE0_PHYS_OFFSET)		:= 0xc0008000
+   zreladdr-$(CONFIG_EP93XX_SDCE0_PHYS_OFFSET)		+= 0xc0008000
 params_phys-$(CONFIG_EP93XX_SDCE0_PHYS_OFFSET)		:= 0xc0000100
 
-   zreladdr-$(CONFIG_EP93XX_SDCE1_PHYS_OFFSET)		:= 0xd0008000
+   zreladdr-$(CONFIG_EP93XX_SDCE1_PHYS_OFFSET)		+= 0xd0008000
 params_phys-$(CONFIG_EP93XX_SDCE1_PHYS_OFFSET)		:= 0xd0000100
 
-   zreladdr-$(CONFIG_EP93XX_SDCE2_PHYS_OFFSET)		:= 0xe0008000
+   zreladdr-$(CONFIG_EP93XX_SDCE2_PHYS_OFFSET)		+= 0xe0008000
 params_phys-$(CONFIG_EP93XX_SDCE2_PHYS_OFFSET)		:= 0xe0000100
 
-   zreladdr-$(CONFIG_EP93XX_SDCE3_ASYNC_PHYS_OFFSET)	:= 0xf0008000
+   zreladdr-$(CONFIG_EP93XX_SDCE3_ASYNC_PHYS_OFFSET)	+= 0xf0008000
 params_phys-$(CONFIG_EP93XX_SDCE3_ASYNC_PHYS_OFFSET)	:= 0xf0000100