x86: config: Increase CONFIG_SYS_BOOTM_LEN to 16MB

The code density of x86_64 is not wonderful. Increase the maximum boot
size and adjust the load address to cope.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/include/configs/coreboot.h b/include/configs/coreboot.h
index a65d89b..fef267f 100644
--- a/include/configs/coreboot.h
+++ b/include/configs/coreboot.h
@@ -49,6 +49,7 @@
 #define CONFIG_FIT
 #undef CONFIG_ZLIB
 #undef CONFIG_GZIP
+#define CONFIG_SYS_BOOTM_LEN		(16 << 20)
 
 /*-----------------------------------------------------------------------
  * Watchdog Configuration
@@ -222,7 +223,7 @@
 
 #define CONFIG_SYS_MEMTEST_START		0x00100000
 #define CONFIG_SYS_MEMTEST_END			0x01000000
-#define CONFIG_SYS_LOAD_ADDR			0x02000000
+#define CONFIG_SYS_LOAD_ADDR			0x20000000
 
 /*-----------------------------------------------------------------------
  * SDRAM Configuration