net: lwip: tftp: update image_load_addr after successful transfer

do_tftpb() parses the load address into a local variable laddr but
never updates the global image_load_addr. Commands that rely on
image_load_addr as their default address (e.g. 'bmp info')
therefore operate on the wrong address when called without
an explicit argument after tftpboot.

Update image_load_addr to laddr only on a successful transfer, so
that it accurately reflects where data was actually loaded.

Fixes: 4d4d783812 ("net: lwip: add TFTP support and tftpboot command")
Signed-off-by: Pranav Sanwal <pranav.sanwal@amd.com>
Reviewed-by: Jerome Forissier <jerome.forissier@arm.com>

net/lwip/tftp.c

@@ -368,6 +368,8 @@ int do_tftpb(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
 
 	if (tftp_loop(eth_get_dev(), laddr, fname, srvip, port) < 0)
 		ret = CMD_RET_FAILURE;
+	else
+		image_load_addr = laddr;
 out:
 	if (arg != net_boot_file_name)
 		free(arg);