staging/ozwpan: Fix NULL vs zero in ozusbsvc1.c (sparse warning)

This patch fixes the warning "Using plain integer as NULL pointer",
generated by sparse, by replacing the offending 0s with NULL.

If the initialization with NULL was unnecessary (due to unconditional
assignment before first use) it was removed.
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/ozwpan/ozusbsvc1.c

@@ -71,7 +71,7 @@ int oz_usb_get_desc_req(void *hpd, u8 req_id, u8 req_type, u8 desc_type,
 	oz_trace("    len = 0x%x\n", len);
 	if (len > 200)
 		len = 200;
-	if (ei == 0)
+	if (ei == NULL)
 		return -1;
 	elt = (struct oz_elt *)ei->data;
 	elt->length = sizeof(struct oz_get_desc_req);
@@ -97,7 +97,7 @@ static int oz_usb_set_config_req(void *hpd, u8 req_id, u8 index)
 	struct oz_elt_buf *eb = &pd->elt_buff;
 	struct oz_elt_info *ei = oz_elt_info_alloc(&pd->elt_buff);
 	struct oz_set_config_req *body;
-	if (ei == 0)
+	if (ei == NULL)
 		return -1;
 	elt = (struct oz_elt *)ei->data;
 	elt->length = sizeof(struct oz_set_config_req);
@@ -118,7 +118,7 @@ static int oz_usb_set_interface_req(void *hpd, u8 req_id, u8 index, u8 alt)
 	struct oz_elt_buf *eb = &pd->elt_buff;
 	struct oz_elt_info *ei = oz_elt_info_alloc(&pd->elt_buff);
 	struct oz_set_interface_req *body;
-	if (ei == 0)
+	if (ei == NULL)
 		return -1;
 	elt = (struct oz_elt *)ei->data;
 	elt->length = sizeof(struct oz_set_interface_req);
@@ -141,7 +141,7 @@ static int oz_usb_set_clear_feature_req(void *hpd, u8 req_id, u8 type,
 	struct oz_elt_buf *eb = &pd->elt_buff;
 	struct oz_elt_info *ei = oz_elt_info_alloc(&pd->elt_buff);
 	struct oz_feature_req *body;
-	if (ei == 0)
+	if (ei == NULL)
 		return -1;
 	elt = (struct oz_elt *)ei->data;
 	elt->length = sizeof(struct oz_feature_req);
@@ -165,7 +165,7 @@ static int oz_usb_vendor_class_req(void *hpd, u8 req_id, u8 req_type,
 	struct oz_elt_buf *eb = &pd->elt_buff;
 	struct oz_elt_info *ei = oz_elt_info_alloc(&pd->elt_buff);
 	struct oz_vendor_class_req *body;
-	if (ei == 0)
+	if (ei == NULL)
 		return -1;
 	elt = (struct oz_elt *)ei->data;
 	elt->length = sizeof(struct oz_vendor_class_req) - 1 + data_len;
@@ -264,7 +264,7 @@ int oz_usb_send_isoc(void *hpd, u8 ep_num, struct urb *urb)
 		int unit_count;
 		int unit_size;
 		int rem;
-		if (ei == 0)
+		if (ei == NULL)
 			return -1;
 		rem = MAX_ISOC_FIXED_DATA;
 		elt = (struct oz_elt *)ei->data;
@@ -359,7 +359,7 @@ void oz_usb_rx(struct oz_pd *pd, struct oz_elt *elt)
 	if (usb_ctx)
 		oz_usb_get(usb_ctx);
 	spin_unlock_bh(&pd->app_lock[OZ_APPID_USB-1]);
-	if (usb_ctx == 0)
+	if (usb_ctx == NULL)
 		return; /* Context has gone so nothing to do. */
 	if (usb_ctx->stopped)
 		goto done;
@@ -391,14 +391,14 @@ void oz_usb_rx(struct oz_pd *pd, struct oz_elt *elt)
 			struct oz_set_config_rsp *body =
 				(struct oz_set_config_rsp *)usb_hdr;
 			oz_hcd_control_cnf(usb_ctx->hport, body->req_id,
-				body->rcode, 0, 0);
+				body->rcode, NULL, 0);
 		}
 		break;
 	case OZ_SET_INTERFACE_RSP: {
 			struct oz_set_interface_rsp *body =
 				(struct oz_set_interface_rsp *)usb_hdr;
 			oz_hcd_control_cnf(usb_ctx->hport,
-				body->req_id, body->rcode, 0, 0);
+				body->req_id, body->rcode, NULL, 0);
 		}
 		break;
 	case OZ_VENDOR_CLASS_RSP: {
@@ -427,7 +427,7 @@ void oz_usb_farewell(struct oz_pd *pd, u8 ep_num, u8 *data, u8 len)
 	if (usb_ctx)
 		oz_usb_get(usb_ctx);
 	spin_unlock_bh(&pd->app_lock[OZ_APPID_USB-1]);
-	if (usb_ctx == 0)
+	if (usb_ctx == NULL)
 		return; /* Context has gone so nothing to do. */
 	if (!usb_ctx->stopped) {
 		oz_trace("Farewell indicated ep = 0x%x\n", ep_num);