usb: phy: twl6030: Remove snprintf() from sysfs call-backs and replace with sysfs_emit()

Since snprintf() has the documented, but still rather strange trait of
returning the length of the data that *would have been* written to the
array if space were available, rather than the arguably more useful
length of data *actually* written, it is usually considered wise to use
something else instead in order to avoid confusion.

In the case of sysfs call-backs, new wrappers exist that do just that.

Link: https://lwn.net/Articles/69419/
Link: https://github.com/KSPP/linux/issues/105
Cc: Hema HK <hemahk@ti.com>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20231213164246.1021885-12-lee@kernel.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/phy/phy-twl6030-usb.c

@@ -179,16 +179,16 @@ static ssize_t vbus_show(struct device *dev,
 
 	switch (twl->linkstat) {
 	case MUSB_VBUS_VALID:
-	       ret = snprintf(buf, PAGE_SIZE, "vbus\n");
+	       ret = sysfs_emit(buf, "vbus\n");
 	       break;
 	case MUSB_ID_GROUND:
-	       ret = snprintf(buf, PAGE_SIZE, "id\n");
+	       ret = sysfs_emit(buf, "id\n");
 	       break;
 	case MUSB_VBUS_OFF:
-	       ret = snprintf(buf, PAGE_SIZE, "none\n");
+	       ret = sysfs_emit(buf, "none\n");
 	       break;
 	default:
-	       ret = snprintf(buf, PAGE_SIZE, "UNKNOWN\n");
+	       ret = sysfs_emit(buf, "UNKNOWN\n");
 	}
 	spin_unlock_irqrestore(&twl->lock, flags);