net: Add wget application

This commit adds a simple wget command that can download files
from http server.

The command syntax is
wget ${loadaddr} <path of the file from server>

Signed-off-by: Duncan Hare <DuncanCHare@yahoo.com>
Signed-off-by: Ying-Chun Liu (PaulLiu) <paul.liu@linaro.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Cc: Christian Gmeiner <christian.gmeiner@gmail.com>
Cc: Joe Hershberger <joe.hershberger@ni.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Ramon Fried <rfried.dev@gmail.com>
Reviewed-by: Ramon Fried <rfried.dev@gmail.com>
diff --git a/cmd/net.c b/cmd/net.c
index addcad3..f6d9f5e 100644
--- a/cmd/net.c
+++ b/cmd/net.c
@@ -125,6 +125,19 @@
 );
 #endif
 
+#if defined(CONFIG_CMD_WGET)
+static int do_wget(struct cmd_tbl *cmdtp, int flag, int argc, char * const argv[])
+{
+	return netboot_common(WGET, cmdtp, argc, argv);
+}
+
+U_BOOT_CMD(
+	wget,   3,      1,      do_wget,
+	"boot image via network using HTTP protocol",
+	"[loadAddress] [[hostIPaddr:]path and image name]"
+);
+#endif
+
 static void netboot_update_env(void)
 {
 	char tmp[22];