doesn't disallow wiping of ssd

[GuiTaek]

Hi, I just created the issue. The code change is ready, every path of the tool leads to this function ssd_checker.is_ssd(). Unfortunately, for all of my usb flash drives, this function shows a "False" which is wrong, isn't it? Next time I find time, I'm going to try to find a tool to detect if it's a flash drive, if you don't have an idea to do it better.