usb: dwc2: gadget: fix debug message for zlp

Print debug message according to zlp direction. Always saying
"Sending" is misleading.
Tested-by: NRobert Baldyga <r.baldyga@samsung.com>
Acked-by: NJohn Youn <johnyoun@synopsys.com>
Signed-off-by: NMian Yousaf Kaukab <yousaf.kaukab@intel.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

drivers/usb/dwc2/gadget.c

@@ -1335,7 +1335,12 @@ static void s3c_hsotg_program_zlp(struct dwc2_hsotg *hsotg,
 	u32 epctl_reg = hs_ep->dir_in ? DIEPCTL(index) : DOEPCTL(index);
 	u32 epsiz_reg = hs_ep->dir_in ? DIEPTSIZ(index) : DOEPTSIZ(index);
 
-	dev_dbg(hsotg->dev, "Sending zero-length packet on ep%d\n", index);
+	if (hs_ep->dir_in)
+		dev_dbg(hsotg->dev, "Sending zero-length packet on ep%d\n",
+									index);
+	else
+		dev_dbg(hsotg->dev, "Receiving zero-length packet on ep%d\n",
+									index);
 
 	writel(DXEPTSIZ_MC(1) | DXEPTSIZ_PKTCNT(1) |
 			DXEPTSIZ_XFERSIZE(0), hsotg->regs +