mx53ard: Remove unused get_board_rev function

No board information is passed for MX53ARD, so remove get_board_rev function.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
diff --git a/board/freescale/mx53ard/mx53ard.c b/board/freescale/mx53ard/mx53ard.c
index c89da13..be32aee 100644
--- a/board/freescale/mx53ard/mx53ard.c
+++ b/board/freescale/mx53ard/mx53ard.c
@@ -37,11 +37,6 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
-u32 get_board_rev(void)
-{
-	return get_cpu_rev();
-}
-
 int dram_init(void)
 {
 	u32 size1, size2;
diff --git a/include/configs/mx53ard.h b/include/configs/mx53ard.h
index daba05f..15dfcb4 100644
--- a/include/configs/mx53ard.h
+++ b/include/configs/mx53ard.h
@@ -34,7 +34,6 @@
 #include <asm/arch/imx-regs.h>
 
 #define CONFIG_CMDLINE_TAG			/* enable passing of ATAGs */
-#define CONFIG_REVISION_TAG
 #define CONFIG_SETUP_MEMORY_TAGS
 #define CONFIG_INITRD_TAG