Fix building using new Xorg 1.14

mibstore functions are no longer supported. This patch removes them
from this driver, following the pattern in
http://patches.openembedded.org/patch/46133/

This checkin shows when/where the changes to the X server were made
that deleted the header mibstore.h and mentions the reasons.
http://lists.x.org/archives/xorg-devel/2012-September/033575.html

Upstream-Status: Pending

Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>

Index: xserver-xorg-video-imx-11.09.01/src/imx_driver.c
===================================================================
--- xserver-xorg-video-imx-11.09.01.orig/src/imx_driver.c
+++ xserver-xorg-video-imx-11.09.01/src/imx_driver.c
@@ -37,7 +37,6 @@
 #include "xf86_OSproc.h"
 
 #include "mipointer.h"
-#include "mibstore.h"
 #include "micmap.h"
 #include "colormapst.h"
 #include "xf86cmap.h"
@@ -722,7 +721,6 @@ imxScreenInit(SCREEN_INIT_ARGS_DECL)
 	/* Initialize for X extensions. */
 	imxExtInit();
 
-	miInitializeBackingStore(pScreen);
 	xf86SetBackingStore(pScreen);
 
 	/* software cursor */