staging: rtl8723bs: Remove comparison to NULL

Remove comparison to NULL in drivers/staging/rtl8723bs/core/rtw_ap.c:1449.
Issue found by checkpatch.pl
Signed-off-by: Wambui Karuga <wambui.karugax@gmail.com>
Link: https://lore.kernel.org/r/20191010132058.20887-1-wambui.karugax@gmail.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rtl8723bs/core/rtw_ap.c

@@ -1447,7 +1447,7 @@ u8 rtw_ap_set_pairwise_key(struct adapter *padapter, struct sta_info *psta)
 	u8 res = _SUCCESS;
 
 	ph2c = rtw_zmalloc(sizeof(struct cmd_obj));
-	if (ph2c == NULL) {
+	if (!ph2c) {
 		res = _FAIL;
 		goto exit;
 	}