How to create a home screen shortcut for a live streaming URL?
If you have a file manager (I use ES File Manager version 4.1.5.5) that can create shortcuts to the desktop, then it is possible to do what you ask.


From ES File Manager, press the file, select More.


Select Open As. A window appears with options. Choose either Audio or Video


A new window will appear with the options to select the app to open the file with. Select Set as the default app, then select your favorite app for playing the m3u streams. The app will open and play the stream. Close the streaming app. 


Select again the file, click More followes by Add to Desktop.
A shortcut will be created; clicking it will open the stream using the app selected during step 3.