Stop using immap_t for guts offset on 85xx

In the future the offsets to various blocks may not be in same location.
Move to using CFG_MPC85xx_GUTS_ADDR as the base of the guts registers
instead of getting it via &immap->im_gur.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
diff --git a/board/mpc8540eval/mpc8540eval.c b/board/mpc8540eval/mpc8540eval.c
index 3b3c8ed..52fe8ca 100644
--- a/board/mpc8540eval/mpc8540eval.c
+++ b/board/mpc8540eval/mpc8540eval.c
@@ -75,7 +75,7 @@
 	uint temp_lbcdll = 0;
 #endif
 #if !defined(CONFIG_RAM_AS_FLASH) || defined(CONFIG_DDR_DLL)
-	volatile ccsr_gur_t *gur= &immap->im_gur;
+	volatile ccsr_gur_t *gur = (void *)(CFG_MPC85xx_GUTS_ADDR);
 #endif
 
 #if defined(CONFIG_DDR_DLL)