ARM: omap: move board specific NAND configs out from ti_armv7_common.h

This patch moves some board specific NAND configs:
- FROM: generic config file 'ti_armv7_common.h'
- TO:   individual board config files using these configs.
So that each board can independently set the value as per its design.

Following configs are affected in this patch:
  CONFIG_SYS_NAND_U_BOOT_OFFS: <refer doc/README.nand>
  CONFIG_CMD_SPL_NAND_OFS: <refer doc/README.falcon>
  CONFIG_SYS_NAND_SPL_KERNEL_OFFS: <refer doc/README.falcon>
  CONFIG_CMD_SPL_WRITE_SIZE: <refer doc/README.falcon>

This patch also updates documentation for few of above NAND configs.

Signed-off-by: Pekon Gupta <pekon@ti.com>
diff --git a/include/configs/pengwyn.h b/include/configs/pengwyn.h
index 8510405..4684ad6 100644
--- a/include/configs/pengwyn.h
+++ b/include/configs/pengwyn.h
@@ -159,6 +159,12 @@
 #define CONFIG_ENV_IS_IN_NAND
 #define CONFIG_ENV_OFFSET		0x260000 /* environment starts here */
 #define CONFIG_SYS_ENV_SECT_SIZE	(128 << 10)	/* 128 KiB */
+/* NAND: SPL falcon mode configs */
+#ifdef CONFIG_SPL_OS_BOOT
+#define CONFIG_CMD_SPL_NAND_OFS		0x240000 /* un-assigned */
+#define CONFIG_SYS_NAND_SPL_KERNEL_OFFS	0x280000
+#define CONFIG_CMD_SPL_WRITE_SIZE	0x2000
+#endif
 
 /*
  * USB configuration.  We enable MUSB support, both for host and for