aiorepl: Handle stream shutdown.

Signed-off-by: Andrew Leech <andrew.leech@planetinnovation.com.au>

micropython/aiorepl/aiorepl.py

@@ -114,6 +114,8 @@ async def task(g=None, prompt="--> "):
             curs = 0  # cursor offset from end of cmd buffer
             while True:
                 b = await s.read(1)
+                if not b:  # Handle EOF/empty read
+                    break
                 pc = c  # save previous character
                 c = ord(b)
                 pt = t  # save previous time