staging: rtl8188eu: refactor rtw_reset_securitypriv()

Move the declaration of 'psec_priv' out of the else path and use it
in the if path as well to improve readability. Also clears line over
80 characters checkpatch warnings.

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Michael Straube <straube.linux@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>