Staging: rtl8192e: Fix Sparse warning of cast to restricted __le16 in rtllib_crypt_tkip.c

This patch fixes the following Sparse warnings in rtllib_crypt_tkip.c-
drivers/staging/rtl8192e/rtllib_crypt_tkip.c:176:16: warning: cast to restricted __le16

Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Reviewed-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>