staging: r8188eu: simplify error handling in recv_func_prehandle

Simplify the error handling in recv_func_prehandle. There's no need to
goto exit, this would be the next statement anyway.

Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Link: https://lore.kernel.org/r/20220515155401.352742-4-martin@kaiser.cx
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>