nfc: microread: constify several pointers

Several functions do not modify pointed data so arguments and local
variables can be const for correctness and safety.

Signed-off-by: Krzysztof Kozlowski <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

drivers/nfc/microread/i2c.c

···
 	skb_trim(skb, MICROREAD_I2C_FRAME_TAILROOM);
 }
 
-static int check_crc(struct sk_buff *skb)
+static int check_crc(const struct sk_buff *skb)
 {
 	int i;
 	u8 crc = 0;

drivers/nfc/microread/microread.c

···
 static void microread_im_transceive_cb(void *context, struct sk_buff *skb,
 				       int err)
 {
-	struct microread_info *info = context;
+	const struct microread_info *info = context;
 
 	switch (info->async_cb_type) {
 	case MICROREAD_CB_TYPE_READER_ALL:
···
 };
 
 int microread_probe(void *phy_id, const struct nfc_phy_ops *phy_ops,
-		    char *llc_name, int phy_headroom, int phy_tailroom,
+		    const char *llc_name, int phy_headroom, int phy_tailroom,
 		    int phy_payload, struct nfc_hci_dev **hdev)
 {
 	struct microread_info *info;

drivers/nfc/microread/microread.h

···
 #define DRIVER_DESC "NFC driver for microread"
 
 int microread_probe(void *phy_id, const struct nfc_phy_ops *phy_ops,
-		    char *llc_name, int phy_headroom, int phy_tailroom,
+		    const char *llc_name, int phy_headroom, int phy_tailroom,
 		    int phy_payload, struct nfc_hci_dev **hdev);
 
 void microread_remove(struct nfc_hci_dev *hdev);