usb: host: pci_quirks: fix memory leak, by adding iounmap

Added iounmap inorder to free memory mapped to pointer before returning

Signed-off-by: Saurabh Sengar <saurabh.truth@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/host/pci-quirks.c b/drivers/usb/host/pci-quirks.c
index 26cb8c8..35af362 100644
--- a/drivers/usb/host/pci-quirks.c
+++ b/drivers/usb/host/pci-quirks.c
@@ -992,7 +992,7 @@
 	if ((ext_cap_offset + sizeof(val)) > len) {
 		/* We're reading garbage from the controller */
 		dev_warn(&pdev->dev, "xHCI controller failing to respond");
-		return;
+		goto iounmap;
 	}
 	val = readl(base + ext_cap_offset);
 
@@ -1055,6 +1055,7 @@
 			 XHCI_MAX_HALT_USEC, val);
 	}
 
+iounmap:
 	iounmap(base);
 }