usb: mtu3: fix the wrong HS mult value

usb_endpoint_maxp() returns actual max packet size, @mult will
always be zero, fix it by using usb_endpoint_maxp_mult() instead
to get mult.

Fixes: 4d79e042 ("usb: mtu3: add support for usb3.1 IP")
Cc: stable@vger.kernel.org
Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/1628836253-7432-3-git-send-email-chunfeng.yun@mediatek.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/mtu3/mtu3_gadget.c

@@ -64,14 +64,12 @@ static int mtu3_ep_enable(struct mtu3_ep *mep)
 	u32 interval = 0;
 	u32 mult = 0;
 	u32 burst = 0;
-	int max_packet;
 	int ret;
 
 	desc = mep->desc;
 	comp_desc = mep->comp_desc;
 	mep->type = usb_endpoint_type(desc);
-	max_packet = usb_endpoint_maxp(desc);
-	mep->maxp = max_packet & GENMASK(10, 0);
+	mep->maxp = usb_endpoint_maxp(desc);
 
 	switch (mtu->g.speed) {
 	case USB_SPEED_SUPER:
@@ -92,7 +90,7 @@ static int mtu3_ep_enable(struct mtu3_ep *mep)
 				usb_endpoint_xfer_int(desc)) {
 			interval = desc->bInterval;
 			interval = clamp_val(interval, 1, 16) - 1;
-			mult = (max_packet & GENMASK(12, 11)) >> 11;
+			mult = usb_endpoint_maxp_mult(desc) - 1;
 		}
 		break;
 	default: