staging: rtl8712: fix missing blank lines after declarations

This commit fixes the following checkpatch warnings:

rtl8712/rtl871x_security.c
    - 275: WARNING: Missing a blank line after declarations
    - 768: WARNING: Missing a blank line after declarations
    - 801: WARNING: Missing a blank line after declarations

Signed-off-by: Marcus Farkas <marcus.farkas@finitebox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>