imx: define per SOC ..._PHYS_OFFSET and use these in favour of PHYS_OFFSET

This is a further step in allowing to build a kernel image for more
than one imx SOC.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
diff --git a/arch/arm/mach-mx25/mx25pdk.c b/arch/arm/mach-mx25/mx25pdk.c
index f4e8b98..10be38e 100644
--- a/arch/arm/mach-mx25/mx25pdk.c
+++ b/arch/arm/mach-mx25/mx25pdk.c
@@ -110,7 +110,7 @@
 	/* Maintainer: Freescale Semiconductor, Inc. */
 	.phys_io	= MX25_AIPS1_BASE_ADDR,
 	.io_pg_offst	= ((MX25_AIPS1_BASE_ADDR_VIRT) >> 18) & 0xfffc,
-	.boot_params    = PHYS_OFFSET + 0x100,
+	.boot_params    = MX25_PHYS_OFFSET + 0x100,
 	.map_io         = mx25_map_io,
 	.init_irq       = mx25_init_irq,
 	.init_machine   = mx25pdk_init,