staging: rtl8188eu: cosmetic: remove useless spaces

Even though these are not reported by checkpatch, they are coding style issues.

Signed-off-by: Luca Ceresoli <luca@lucaceresoli.net>
Cc: Greg Kroah-Hartman <gregkh@linux.com>
Cc: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>