When trying to build some modules with the "hint" branch of imx tree,
they're now failing to build at modpost with an error like this :

  OBJCOPY arch/arm/boot/zImage
  Kernel: arch/arm/boot/zImage is ready
  Building modules, stage 2.
  MODPOST 69 modules
ERROR: "imx_ioremap" [sound/soc/imx/snd-soc-imx.ko] undefined!
ERROR: "imx_ioremap" [drivers/usb/gadget/fsl_usb2_udc.ko] undefined!
make[1]: *** [__modpost] Error 1
make: *** [modules] Error 2

It seems to be caused by commit f548897ffc0510885af27e22a11f449fe5e0cbbd,
which introduced imx_ioremap without EXPORT_SYMBOL.

Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>
Index: linux-2.6-submit/arch/arm/plat-mxc/system.c
===================================================================
--- linux-2.6-submit.orig/arch/arm/plat-mxc/system.c	2011-10-18 01:35:32.000000000 +0200
+++ linux-2.6-submit/arch/arm/plat-mxc/system.c	2011-10-18 11:56:45.000000000 +0200
@@ -21,6 +21,7 @@
 #include <linux/io.h>
 #include <linux/err.h>
 #include <linux/delay.h>
+#include <linux/module.h>
 
 #include <mach/hardware.h>
 #include <mach/common.h>
@@ -30,6 +31,7 @@
 
 void (*imx_idle)(void) = NULL;
 void __iomem *(*imx_ioremap)(unsigned long, size_t, unsigned int) = NULL;
+EXPORT_SYMBOL(imx_ioremap);
 
 static void __iomem *wdog_base;