asyncio doc: fix references in subprocess doc

Doc/library/asyncio-subprocess.rst

@@ -8,14 +8,14 @@ Create a subprocess
 
 .. function:: create_subprocess_shell(cmd, stdin=None, stdout=None, stderr=None, loop=None, limit=None, \*\*kwds)
 
-   Run the shell command *cmd* given as a string. Return a :class:`Process`
+   Run the shell command *cmd* given as a string. Return a :class:`~asyncio.subprocess.Process`
    instance.
 
    This function returns a :ref:`coroutine object <coroutine>`.
 
 .. function:: create_subprocess_exec(\*args, stdin=None, stdout=None, stderr=None, loop=None, limit=None, \*\*kwds)
 
-   Create a subprocess. Return a :class:`Process` instance.
+   Create a subprocess. Return a :class:`~asyncio.subprocess.Process` instance.
 
    This function returns a :ref:`coroutine object <coroutine>`.