Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>

drivers/net/can/softing/softing.h

@@ -22,7 +22,7 @@ struct softing_priv {
 	struct softing *card;
 	struct {
 		int pending;
-		/* variables wich hold the circular buffer */
+		/* variables which hold the circular buffer */
 		int echo_put;
 		int echo_get;
 	} tx;

drivers/net/can/softing/softing_main.c

@@ -218,7 +218,7 @@ static int softing_handle_1(struct softing *card)
 	ptr = buf;
 	cmd = *ptr++;
 	if (cmd == 0xff)
-		/* not quite usefull, probably the card has got out */
+		/* not quite useful, probably the card has got out */
 		return 0;
 	netdev = card->net[0];
 	if (cmd & CMD_BUS2)