powerpc/mpc8536ds: Add eSPI support for MPC8536DS

1. The SD_DATA[4:7] signals are shared with the SPI chip selects on 8536DS,
   so don't set MPC85xx_PMUXCR_SD_DATA that config eSDHC data bus-width
   to 4-bit and enable SPI signals.
2. Add eSPI controller and SPI-FLASH definition.

Signed-off-by: Xie Xiaobo <r63061@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
diff --git a/board/freescale/mpc8536ds/mpc8536ds.c b/board/freescale/mpc8536ds/mpc8536ds.c
index b292e13..2beea34 100644
--- a/board/freescale/mpc8536ds/mpc8536ds.c
+++ b/board/freescale/mpc8536ds/mpc8536ds.c
@@ -1,5 +1,5 @@
 /*
- * Copyright 2008-2010 Freescale Semiconductor, Inc.
+ * Copyright 2008-2010, 2011 Freescale Semiconductor, Inc.
  *
  * See file CREDITS for list of people who contributed to this
  * project.
@@ -49,10 +49,8 @@
 	volatile ccsr_gur_t *gur = (void *)(CONFIG_SYS_MPC85xx_GUTS_ADDR);
 
 	setbits_be32(&gur->pmuxcr,
-			(MPC85xx_PMUXCR_SD_DATA |
-			 MPC85xx_PMUXCR_SDHC_CD |
+			(MPC85xx_PMUXCR_SDHC_CD |
 			 MPC85xx_PMUXCR_SDHC_WP));
-
 #endif
 	return 0;
 }