Staging: rtl8188eu: Fix warning of braces are not necessary.

This patch fixes the warning of "braces are not necessary for single
statement blocks" in file rtw_ieee80211.c.

Signed-off-by: Elena Oat <oat.elena@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>