staging: r8188eu: drop return value from receive_disconnect

The receive_disconnect function always returns _SUCCESS. None of the
callers checks the return value. We can remove it.

Tested-by: Philipp Hortmann <philipp.g.hortmann@gmail.com> # Edimax N150
Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Link: https://lore.kernel.org/r/20220626180734.287137-1-martin@kaiser.cx


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>