staging: rtl8188eu: remove exit label from rtw_alloc_stainfo

Remove exit label from rtw_alloc_stainfo and simply return NULL
instead of goto exit.

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Michael Straube <straube.linux@gmail.com>
Link: https://lore.kernel.org/r/20191027130604.68379-1-straube.linux@gmail.com


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