x86: x86-common.h: Add generic FS commands

This patch adds the generic FS commands (ls, load) to all x86 boards.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Miao Yan <yanmiaobest@gmail.com>
Cc: Bin Meng <bmeng.cn@gmail.com>
Cc: Simon Glass <sjg@chromium.org>
Acked-by: Bin Meng <bmeng.cn@gmail.com>

include/configs/x86-common.h

@@ -100,6 +100,7 @@
  * Command line configuration.
  */
 #define CONFIG_CMD_DATE
+#define CONFIG_CMD_FS_GENERIC
 #define CONFIG_CMD_FPGA_LOADMK
 #define CONFIG_CMD_IO
 #define CONFIG_CMD_IRQ