Staging: rtl8712: Coding style warnings fix for block comments

This patch is to the rtl871x_ioctl_linux.c file that fixes up following
warnings reported by checkpatch.pl :

-Block comments use * on subsequent lines
-Block comments use a trailing */ on a separate line

Signed-off-by: Punit Vara <punitvara@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>