staging: rtl8192u: ieee80211: ieee80211_rx.c: Remove unnecessary braces.

Remove braces around single statement block.
Issue found by checkpatch.pl

WARNING: braces {} are not necessary for a single statement block

Signed-off-by: Sanjana Sanikommu <sanjana99reddy99@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>