boston: Bump CONFIG_SYS_BOOTM_LEN to 64MiB

The default value of CONFIG_SYS_BOOTM_LEN is too small for typical
boston Linux kernels. Increase the limit to 64MB, which covers current
kernels with plenty of breathing room.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

include/configs/boston.h

@@ -7,6 +7,11 @@
 #ifndef __CONFIGS_BOSTON_H__
 #define __CONFIGS_BOSTON_H__
 
+/*
+ * General board configuration
+ */
+#define CONFIG_SYS_BOOTM_LEN		(64 * 1024 * 1024)
+
 /*
  * CPU
  */