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

This patch fixes the warning of "braces {} are not necessary for any arm
of this statement" in file rtw_ioctl_set.c. The braces are removed in
three places.

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