powerpc/85xx: Bump up the CONFIG_SYS_BOOTM_LEN to 16M on FSL 85xx boards

CONFIG_SYS_BOOTMAPSZ has been 16M on these boards for some time so we
should also allow the kernel image to be up to 16M decompressed.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
diff --git a/include/configs/corenet_ds.h b/include/configs/corenet_ds.h
index d1ac756..23bbd42 100644
--- a/include/configs/corenet_ds.h
+++ b/include/configs/corenet_ds.h
@@ -532,6 +532,7 @@
  * the maximum mapped by the Linux kernel during initialization.
  */
 #define CONFIG_SYS_BOOTMAPSZ	(16 << 20)	/* Initial Memory map for Linux*/
+#define CONFIG_SYS_BOOTM_LEN	(16 << 20)	/* Increase max gunzip size */
 
 #ifdef CONFIG_CMD_KGDB
 #define CONFIG_KGDB_BAUDRATE	230400	/* speed to run kgdb serial port */