powerpc/mpc85xx:Increase binary size for P, B & T series boards.

u-boot binary size for Freescale mpc85xx platforms is 512KB.
This has been reached to upper limit for some of the platforms causig
linker error.

So, Increase the u-boot binary size to 768KB.

Signed-off-by: York Sun <yorksun@freescale.com>
Signed-off-by: Prabhakar Kushwaha <prabhakar@freescale.com>
diff --git a/board/freescale/c29xpcie/README b/board/freescale/c29xpcie/README
index 430f0824..3bc396b 100644
--- a/board/freescale/c29xpcie/README
+++ b/board/freescale/c29xpcie/README
@@ -62,9 +62,9 @@
 
 2. Program u-boot.bin into NOR flash
 	=> tftp $loadaddr $uboot
-	=> protect off eff80000 +$filesize
-	=> erase eff80000 +$filesize
-	=> cp.b $loadaddr eff80000 $filesize
+	=> protect off eff40000 +$filesize
+	=> erase eff40000 +$filesize
+	=> cp.b $loadaddr eff40000 $filesize
 
 3. Check SW5[1:4]= 1111 and SW5[6]=0, then power on.
 
@@ -73,9 +73,9 @@
 There are four banks in C29XPCIE board, example to change bank booting:
 1. Program u-boot.bin into alternate NOR bank
 	=> tftp $loadaddr $uboot
-	=> protect off e9f80000 +$filesize
-	=> erase e9f80000 +$filesize
-	=> cp.b $loadaddr e9f80000 $filesize
+	=> protect off e9f40000 +$filesize
+	=> erase e9f40000 +$filesize
+	=> cp.b $loadaddr e9f40000 $filesize
 
 2. Switch to alternate NOR bank
 	=> cpld_cmd reset altbank [bank]