mx7dsabresd: Remove get_board_rev()

get_board_rev() is not actually providing the board revision.

It just returns the CPU revision instead.

As the CPU revision is already printed on boot, there is no
reason to have get_board_rev(), so let's remove it.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
diff --git a/board/freescale/mx7dsabresd/mx7dsabresd.c b/board/freescale/mx7dsabresd/mx7dsabresd.c
index d7e4589..bb823f5 100644
--- a/board/freescale/mx7dsabresd/mx7dsabresd.c
+++ b/board/freescale/mx7dsabresd/mx7dsabresd.c
@@ -485,11 +485,6 @@
 	return 0;
 }
 
-u32 get_board_rev(void)
-{
-	return get_cpu_rev();
-}
-
 int checkboard(void)
 {
 	puts("Board: i.MX7D SABRESD\n");