bdinfo: Update the file comments

Update the comment at the top of the file to indicate what this file does.
Also drop the line at the bottom and an unnecessary header include.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

cmd/bdinfo.c

@@ -1,19 +1,17 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
+ * Implements the 'bd' command to show board information
+ *
  * (C) Copyright 2003
  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  */
 
-/*
- * Boot support
- */
 #include <common.h>
 #include <command.h>
 #include <env.h>
 #include <net.h>
 #include <vsprintf.h>
 #include <asm/cache.h>
-#include <linux/compiler.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
@@ -104,8 +102,6 @@ int do_bdinfo(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
 	return 0;
 }
 
-/* -------------------------------------------------------------------- */
-
 U_BOOT_CMD(
 	bdinfo,	1,	1,	do_bdinfo,
 	"print Board Info structure",